From d2db617f248b71a2194aaf8e03918a3ea9150ab6 Mon Sep 17 00:00:00 2001
From: Eric Hills <53243273+ebhills@users.noreply.github.com>
Date: Sun, 6 Sep 2026 21:43:43 -0500
Subject: [PATCH] feat: add column semantics to wrangle registry

---
 registry/CONTRACT.md                          |  27 ++-
 registry/reports/runtime-reconciliation.json  |  44 +++-
 registry/reports/runtime-reconciliation.md    |   5 +-
 registry/schema/wrangle-entry.schema.json     |  18 ++
 registry/wrangles/_root/drop.md               |   5 +
 registry/wrangles/_root/rename.md             |  12 +
 registry/wrangles/extract/date-range.md       |   9 +
 registry/wrangles/standardize/clean.md        |  14 ++
 wrangles-docs/package.json                    |   3 +-
 wrangles-docs/scripts/compile-registry.cjs    | 142 +++++++++++-
 .../scripts/compile-registry.test.cjs         | 211 ++++++++++++++++++
 .../static/registry/contracts/accordion.json  |   2 +-
 .../static/registry/contracts/batch.json      |   2 +-
 .../static/registry/contracts/classify.json   |   2 +-
 .../registry/contracts/clean-whitespaces.json |   2 +-
 .../registry/contracts/compare/lists.json     |   2 +-
 .../registry/contracts/compare/text.json      |   2 +-
 .../registry/contracts/compute/case-when.json |   2 +-
 .../compute/score-search-results.json         |   2 +-
 .../static/registry/contracts/concurrent.json |   2 +-
 .../registry/contracts/convert/case.json      |   2 +-
 .../registry/contracts/convert/data-type.json |   2 +-
 .../convert/fraction-to-decimal.json          |   2 +-
 .../registry/contracts/convert/from-json.json |   2 +-
 .../registry/contracts/convert/from-yaml.json |   2 +-
 .../registry/contracts/convert/to-json.json   |   2 +-
 .../registry/contracts/convert/to-yaml.json   |   2 +-
 .../static/registry/contracts/copy.json       |   2 +-
 .../registry/contracts/create/bins.json       |   2 +-
 .../registry/contracts/create/column.json     |   2 +-
 .../registry/contracts/create/embeddings.json |   2 +-
 .../registry/contracts/create/guid.json       |   2 +-
 .../registry/contracts/create/hash.json       |   2 +-
 .../registry/contracts/create/index.json      |   2 +-
 .../registry/contracts/create/jinja.json      |   2 +-
 .../registry/contracts/create/uuid.json       |   2 +-
 .../registry/contracts/date-calculator.json   |   2 +-
 .../static/registry/contracts/drop.json       |  11 +-
 .../static/registry/contracts/explode.json    |   2 +-
 .../registry/contracts/extract/address.json   |   2 +-
 .../static/registry/contracts/extract/ai.json |   2 +-
 .../contracts/extract/attributes.json         |   2 +-
 .../registry/contracts/extract/brackets.json  |   2 +-
 .../registry/contracts/extract/codes.json     |   2 +-
 .../registry/contracts/extract/custom.json    |   2 +-
 .../contracts/extract/date-properties.json    |   2 +-
 .../contracts/extract/date-range.json         |  14 +-
 .../registry/contracts/extract/html.json      |   2 +-
 .../contracts/extract/properties.json         |   2 +-
 .../registry/contracts/extract/regex.json     |   2 +-
 .../static/registry/contracts/filter.json     |   2 +-
 .../registry/contracts/format/dates.json      |   2 +-
 .../static/registry/contracts/format/pad.json |   2 +-
 .../registry/contracts/format/prefix.json     |   2 +-
 .../contracts/format/price-breaks.json        |   2 +-
 .../contracts/format/remove-duplicates.json   |   2 +-
 .../contracts/format/significant-figures.json |   2 +-
 .../registry/contracts/format/suffix.json     |   2 +-
 .../registry/contracts/format/trim.json       |   2 +-
 .../registry/contracts/generate/ai.json       |   2 +-
 .../registry/contracts/huggingface.json       |   2 +-
 .../static/registry/contracts/log.json        |   2 +-
 .../static/registry/contracts/lookup.json     |   2 +-
 .../static/registry/contracts/math.json       |   2 +-
 .../static/registry/contracts/maths.json      |   2 +-
 .../static/registry/contracts/matrix.json     |   2 +-
 .../registry/contracts/merge/coalesce.json    |   2 +-
 .../registry/contracts/merge/concatenate.json |   2 +-
 .../contracts/merge/dictionaries.json         |   2 +-
 .../contracts/merge/key-value-pairs.json      |   2 +-
 .../registry/contracts/merge/lists.json       |   2 +-
 .../registry/contracts/merge/to-dict.json     |   2 +-
 .../registry/contracts/merge/to-list.json     |   2 +-
 .../static/registry/contracts/python.json     |   2 +-
 .../static/registry/contracts/recipe.json     |   2 +-
 .../static/registry/contracts/reindex.json    |   2 +-
 .../registry/contracts/remove-words.json      |   2 +-
 .../static/registry/contracts/rename.json     |  23 +-
 .../static/registry/contracts/replace.json    |   2 +-
 .../static/registry/contracts/round.json      |   2 +-
 .../registry/contracts/search/find-links.json |   2 +-
 .../search/retrieve-link-content.json         |   2 +-
 .../registry/contracts/select/columns.json    |   2 +-
 .../contracts/select/dictionary-element.json  |   2 +-
 .../registry/contracts/select/element.json    |   2 +-
 .../registry/contracts/select/group-by.json   |   2 +-
 .../registry/contracts/select/head.json       |   2 +-
 .../contracts/select/highest-confidence.json  |   2 +-
 .../registry/contracts/select/left.json       |   2 +-
 .../registry/contracts/select/length.json     |   2 +-
 .../contracts/select/list-element.json        |   2 +-
 .../registry/contracts/select/right.json      |   2 +-
 .../registry/contracts/select/sample.json     |   2 +-
 .../registry/contracts/select/substring.json  |   2 +-
 .../registry/contracts/select/tail.json       |   2 +-
 .../registry/contracts/select/threshold.json  |   2 +-
 .../static/registry/contracts/similarity.json |   2 +-
 .../static/registry/contracts/sort.json       |   2 +-
 .../registry/contracts/split/dictionary.json  |   2 +-
 .../static/registry/contracts/split/list.json |   2 +-
 .../static/registry/contracts/split/text.json |   2 +-
 .../registry/contracts/split/tokenize.json    |   2 +-
 .../static/registry/contracts/sql.json        |   2 +-
 .../registry/contracts/standardize.json       |   2 +-
 .../registry/contracts/standardize/clean.json |  26 ++-
 .../contracts/standardize/custom.json         |   2 +-
 .../static/registry/contracts/translate.json  |   2 +-
 .../static/registry/contracts/transpose.json  |   2 +-
 .../static/registry/contracts/try.json        |   2 +-
 wrangles-docs/static/registry/index.md        |   2 +-
 wrangles-docs/static/registry/manifest.json   | 210 ++++++++---------
 .../registry/runtime/reconciliation.json      |   2 +-
 .../schema/wrangle-contract.schema.json       |  30 ++-
 .../registry/schema/wrangle-entry.schema.json |  28 +++
 .../static/registry/wrangles/_root/drop.md    |   5 +
 .../static/registry/wrangles/_root/rename.md  |  12 +
 .../registry/wrangles/extract/date-range.md   |   9 +
 .../registry/wrangles/standardize/clean.md    |  14 ++
 .../registry/recipe-writer.schema.json        |  49 +++-
 .../schemas/recipes/registry/schema.json      |  66 +++++-
 120 files changed, 948 insertions(+), 231 deletions(-)
 create mode 100644 wrangles-docs/scripts/compile-registry.test.cjs

diff --git a/registry/CONTRACT.md b/registry/CONTRACT.md
index b2d02a9..d78dcda 100644
--- a/registry/CONTRACT.md
+++ b/registry/CONTRACT.md
@@ -200,6 +200,28 @@ Parameter records contain human guidance plus a JSON Schema fragment. Every
 runtime-owned parameter fact must reconcile with the pinned manifest and be
 traceable to the named runtime symbol.
 
+Parameters whose values directly identify dataframe columns may also declare
+optional `column_semantics`. Its `role` is `reference` when the value selects a
+column that must exist before the step and `destination` when the value names a
+column where the step writes results. Its `cardinality` is `scalar`, `list`, or
+`scalar_or_list`, matching the accepted JSON Schema shape; nullability remains
+part of the parameter's `schema` and does not change cardinality. The compiler
+copies this object into each per-wrangle contract and emits it as the
+`x-wrangles-column` annotation on the corresponding generated recipe-schema
+property.
+
+Column semantics are valid only when every non-null value shape exposes column
+identifiers directly: a scalar is a string or integer, and a list is an array
+whose `items` schema accepts only strings or integers. Unconstrained arrays,
+nested arrays, objects, mappings, and `$ref`/`allOf` shapes are not annotated.
+Those forms require a future locator vocabulary that can say where within the
+value the column identifier appears (for example, in a mapping key).
+
+This metadata describes column-name syntax, not dataframe state transitions. A
+destination may create, overwrite, or conditionally reuse a column. The current
+Registry has no validated effect vocabulary for add, rename, or remove, so
+consumers must not infer those effects from `role` or parameter names.
+
 Every parameter also declares one `param_group` from a small shared vocabulary:
 
 - `I/O` identifies input and output columns or structures.
@@ -309,9 +331,12 @@ terminated by one newline (`utf8-newline-separated-sorted-v1`).
 
 ## Versioning and lifecycle
 
-The pre-production Registry version is `0.2.0`. Version `0.2.0` makes the
+The pre-production Registry version is `0.2.1`. Version `0.2.0` makes the
 fail-closed Recipe Writer eligibility decision required for every entry and
 adds the compiled-contract and integrity metadata consumed by Registry clients.
+Version `0.2.1` introduces optional column-role and cardinality metadata plus
+explicit direct-item schemas for its representative list parameters, while
+retaining the `0.2` entry schema compatibility series.
 A production release will
 contain:
 
diff --git a/registry/reports/runtime-reconciliation.json b/registry/reports/runtime-reconciliation.json
index f7c7f44..47f7123 100644
--- a/registry/reports/runtime-reconciliation.json
+++ b/registry/reports/runtime-reconciliation.json
@@ -1,7 +1,7 @@
 {
   "format": "wrangles-registry-reconciliation",
   "format_version": "0.2",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "runtime_source": {
     "repository": "https://github.com/wrangleworks/WranglesPY",
     "version": "1.20.2",
@@ -1089,6 +1089,9 @@
           "code": "schema_constraint_difference",
           "parameter": "columns",
           "registry_schema": {
+            "items": {
+              "type": "string"
+            },
             "type": [
               "string",
               "array"
@@ -3254,6 +3257,12 @@
           "code": "schema_constraint_difference",
           "parameter": "input",
           "registry_schema": {
+            "items": {
+              "type": [
+                "string",
+                "integer"
+              ]
+            },
             "type": [
               "string",
               "integer",
@@ -3273,6 +3282,9 @@
           "code": "schema_constraint_difference",
           "parameter": "output",
           "registry_schema": {
+            "items": {
+              "type": "string"
+            },
             "type": [
               "string",
               "array",
@@ -4261,6 +4273,30 @@
             "type": "boolean"
           }
         },
+        {
+          "code": "schema_constraint_difference",
+          "parameter": "input",
+          "registry_schema": {
+            "items": {
+              "type": [
+                "string",
+                "integer"
+              ]
+            },
+            "type": [
+              "string",
+              "integer",
+              "array"
+            ]
+          },
+          "docstring_schema": {
+            "type": [
+              "string",
+              "integer",
+              "array"
+            ]
+          }
+        },
         {
           "code": "schema_constraint_difference",
           "parameter": "normalization",
@@ -4293,6 +4329,12 @@
           "code": "schema_constraint_difference",
           "parameter": "output",
           "registry_schema": {
+            "items": {
+              "type": [
+                "string",
+                "integer"
+              ]
+            },
             "type": [
               "string",
               "integer",
diff --git a/registry/reports/runtime-reconciliation.md b/registry/reports/runtime-reconciliation.md
index 355e1bb..3d7a21b 100644
--- a/registry/reports/runtime-reconciliation.md
+++ b/registry/reports/runtime-reconciliation.md
@@ -4,7 +4,7 @@ Generated file. Do not edit directly.
 
 - Runtime version: `1.20.2`
 - Runtime source: [`7916bf158e8b7e561270a1bea7b808f88956edc4`](https://github.com/wrangleworks/WranglesPY/commit/7916bf158e8b7e561270a1bea7b808f88956edc4)
-- Registry version: `0.2.0`
+- Registry version: `0.2.1`
 - Runtime entries: 98
 - Embedded Python schema docstrings: 96
 - Existing quasi-registry records: 93
@@ -119,7 +119,7 @@ capabilities must reconcile; individual records can be curated in place later.
 | `split.tokenize` | `split.tokenize` | verified | 0 | 1 |
 | `sql` | `sql` | verified | 0 | 3 |
 | `standardize` | `standardize` | verified | 0 | 3 |
-| `standardize.clean` | `standardize.clean` | verified | 0 | 12 |
+| `standardize.clean` | `standardize.clean` | verified | 0 | 13 |
 | `standardize.custom` | `standardize.custom` | verified | 0 | 3 |
 | `translate` | `translate` | verified | 0 | 1 |
 | `transpose` | `transpose` | verified | 0 | 1 |
@@ -365,6 +365,7 @@ capabilities must reconcile; individual records can be curated in place later.
 | `standardize.clean` | schema_constraint_difference | `collapse_whitespace` | See the JSON report for both schema fragments. |
 | `standardize.clean` | schema_constraint_difference | `fix_character_width` | See the JSON report for both schema fragments. |
 | `standardize.clean` | schema_constraint_difference | `fix_encoding` | See the JSON report for both schema fragments. |
+| `standardize.clean` | schema_constraint_difference | `input` | See the JSON report for both schema fragments. |
 | `standardize.clean` | schema_constraint_difference | `normalization` | See the JSON report for both schema fragments. |
 | `standardize.clean` | schema_constraint_difference | `output` | See the JSON report for both schema fragments. |
 | `standardize.clean` | schema_constraint_difference | `preserve_line_breaks` | See the JSON report for both schema fragments. |
diff --git a/registry/schema/wrangle-entry.schema.json b/registry/schema/wrangle-entry.schema.json
index 74156bc..036a617 100644
--- a/registry/schema/wrangle-entry.schema.json
+++ b/registry/schema/wrangle-entry.schema.json
@@ -188,10 +188,28 @@
             "Details"
           ]
         },
+        "column_semantics": {
+          "$ref": "#/$defs/column_semantics"
+        },
         "runtime_default": {},
         "schema": {"type": "object", "minProperties": 1}
       }
     },
+    "column_semantics": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["role", "cardinality"],
+      "properties": {
+        "role": {
+          "enum": ["reference", "destination"],
+          "description": "Whether the parameter selects columns that exist before the step or names columns where the step writes results."
+        },
+        "cardinality": {
+          "enum": ["scalar", "list", "scalar_or_list"],
+          "description": "Whether the parameter accepts one direct string/integer column identifier, an array whose direct items are string/integer identifiers, or either shape. Nullability is defined separately by the parameter schema; object and mapping-key locations require a future locator vocabulary."
+        }
+      }
+    },
     "example": {
       "type": "object",
       "additionalProperties": false,
diff --git a/registry/wrangles/_root/drop.md b/registry/wrangles/_root/drop.md
index 7435a7e..9c5c190 100644
--- a/registry/wrangles/_root/drop.md
+++ b/registry/wrangles/_root/drop.md
@@ -34,10 +34,15 @@ parameters:
     description: Name of the column(s) to drop.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar_or_list
     schema:
       type:
         - string
         - array
+      items:
+        type: string
 examples: []
 sources:
   - id: runtime
diff --git a/registry/wrangles/_root/rename.md b/registry/wrangles/_root/rename.md
index 2dee332..e90e42e 100644
--- a/registry/wrangles/_root/rename.md
+++ b/registry/wrangles/_root/rename.md
@@ -35,6 +35,9 @@ parameters:
     description: Name or list of input columns.
     required: false
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar_or_list
     runtime_default: null
     schema:
       type:
@@ -42,16 +45,25 @@ parameters:
         - integer
         - array
         - 'null'
+      items:
+        type:
+          - string
+          - integer
   - name: output
     description: Name or list of output columns.
     required: false
     param_group: I/O
+    column_semantics:
+      role: destination
+      cardinality: scalar_or_list
     runtime_default: null
     schema:
       type:
         - string
         - array
         - 'null'
+      items:
+        type: string
   - name: wrangles
     description: >-
       Use wrangles to transform the column names. The input is named 'columns' and the final result
diff --git a/registry/wrangles/extract/date-range.md b/registry/wrangles/extract/date-range.md
index 7a4d4f3..ee36c9d 100644
--- a/registry/wrangles/extract/date-range.md
+++ b/registry/wrangles/extract/date-range.md
@@ -34,18 +34,27 @@ parameters:
     description: Name of the start date column.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar
     schema:
       type: string
   - name: end_time
     description: Name of the end date column.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar
     schema:
       type: string
   - name: output
     description: Name of the output column.
     required: true
     param_group: I/O
+    column_semantics:
+      role: destination
+      cardinality: scalar
     schema:
       type: string
   - name: range
diff --git a/registry/wrangles/standardize/clean.md b/registry/wrangles/standardize/clean.md
index fced91a..1eb6053 100644
--- a/registry/wrangles/standardize/clean.md
+++ b/registry/wrangles/standardize/clean.md
@@ -36,15 +36,25 @@ parameters:
     description: Name or list of input columns.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar_or_list
     schema:
       type:
         - string
         - integer
         - array
+      items:
+        type:
+          - string
+          - integer
   - name: output
     description: Name or list of output columns. Defaults to overwriting input.
     required: false
     param_group: I/O
+    column_semantics:
+      role: destination
+      cardinality: scalar_or_list
     runtime_default: null
     schema:
       type:
@@ -52,6 +62,10 @@ parameters:
         - integer
         - array
         - 'null'
+      items:
+        type:
+          - string
+          - integer
   - name: fix_encoding
     description: Repair mojibake and other reversible encoding errors.
     required: false
diff --git a/wrangles-docs/package.json b/wrangles-docs/package.json
index 2d2eb1e..db6f554 100644
--- a/wrangles-docs/package.json
+++ b/wrangles-docs/package.json
@@ -13,7 +13,8 @@
     "clear": "docusaurus clear",
     "compile:registry": "node ./scripts/compile-registry.cjs",
     "bootstrap:registry": "node ./scripts/bootstrap-registry.cjs",
-    "check:registry": "node ./scripts/compile-registry.cjs --check",
+    "test:registry": "node --test ./scripts/compile-registry.test.cjs",
+    "check:registry": "npm run test:registry && node ./scripts/compile-registry.cjs --check",
     "prebuild": "npm run compile:registry",
     "generate:wrangle-catalog": "node ./scripts/generate-wrangle-catalog.cjs",
     "serve": "docusaurus serve",
diff --git a/wrangles-docs/scripts/compile-registry.cjs b/wrangles-docs/scripts/compile-registry.cjs
index 348c6fa..7a7241d 100644
--- a/wrangles-docs/scripts/compile-registry.cjs
+++ b/wrangles-docs/scripts/compile-registry.cjs
@@ -5,7 +5,7 @@ const path = require('node:path');
 const crypto = require('node:crypto');
 const yaml = require('js-yaml');
 
-const REGISTRY_VERSION = '0.2.0';
+const REGISTRY_VERSION = '0.2.1';
 const ENTRY_SCHEMA_VERSION = '0.2';
 const PUBLIC_ORIGIN = 'https://docs.wrangles.com';
 const RECIPE_WRITER_BASELINE_COUNT = 88;
@@ -65,6 +65,8 @@ const PARAM_GROUP_ORDER = [
   'Errors',
   'Details',
 ];
+const COLUMN_ROLES = ['reference', 'destination'];
+const COLUMN_CARDINALITIES = ['scalar', 'list', 'scalar_or_list'];
 
 const generatedFiles = new Map();
 const errors = [];
@@ -403,6 +405,125 @@ function validateSchemaFragment(fragment, source, label) {
   }
 }
 
+function directColumnSchemaShapes(fragment) {
+  const shapes = new Set();
+  const messages = [];
+
+  function visit(value, location, listItem = false) {
+    if (!isObject(value)) {
+      messages.push(`${location} must be an object schema`);
+      return;
+    }
+    if (typeof value.$ref === 'string') {
+      messages.push(
+        `${location} uses $ref; indirect column locations require a future locator vocabulary`,
+      );
+      return;
+    }
+    if (hasOwn(value, 'allOf')) {
+      messages.push(
+        `${location} uses allOf; indirect column locations require a future locator vocabulary`,
+      );
+      return;
+    }
+
+    const unions = ['anyOf', 'oneOf'].filter((keyword) => hasOwn(value, keyword));
+    if (unions.length > 1 || (unions.length === 1 && hasOwn(value, 'type'))) {
+      messages.push(`${location} must use either type or one anyOf/oneOf union`);
+      return;
+    }
+    if (unions.length === 1) {
+      const keyword = unions[0];
+      if (!Array.isArray(value[keyword])) {
+        messages.push(`${location}.${keyword} must be an array`);
+        return;
+      }
+      value[keyword].forEach((option, index) =>
+        visit(option, `${location}.${keyword}[${index}]`, listItem));
+      return;
+    }
+
+    const declaredTypes = Array.isArray(value.type) ? value.type : [value.type];
+    for (const type of declaredTypes) {
+      if (type === 'null' && !listItem) continue;
+      if (type === 'string' || type === 'integer') {
+        shapes.add(listItem ? 'list' : 'scalar');
+        continue;
+      }
+      if (type === 'array' && !listItem) {
+        if (!isObject(value.items)) {
+          messages.push(
+            `${location} array items must be explicitly limited to string/integer column identifiers`,
+          );
+        } else {
+          visit(value.items, `${location}.items`, true);
+        }
+        continue;
+      }
+
+      const valueLocation = listItem ? 'array item' : 'parameter value';
+      messages.push(
+        `${location} accepts unsupported ${valueLocation} type ${String(type)}; ` +
+          'object, mapping, nested-list, and other indirect locations require a future locator vocabulary',
+      );
+    }
+  }
+
+  visit(fragment, 'schema');
+  return {shapes, messages};
+}
+
+function validateColumnSemantics(parameter) {
+  if (!hasOwn(parameter, 'column_semantics')) return [];
+
+  const semantics = parameter.column_semantics;
+  if (!isObject(semantics)) return ['column_semantics must be an object'];
+
+  const messages = [];
+  const allowed = new Set(['role', 'cardinality']);
+  for (const key of Object.keys(semantics)) {
+    if (!allowed.has(key)) messages.push(`column_semantics has unknown field ${key}`);
+  }
+  for (const key of allowed) {
+    if (!hasOwn(semantics, key)) messages.push(`column_semantics.${key} is required`);
+  }
+  if (!COLUMN_ROLES.includes(semantics.role)) {
+    messages.push(`column_semantics.role must be one of: ${COLUMN_ROLES.join(', ')}`);
+  }
+  if (!COLUMN_CARDINALITIES.includes(semantics.cardinality)) {
+    messages.push(
+      `column_semantics.cardinality must be one of: ${COLUMN_CARDINALITIES.join(', ')}`,
+    );
+    return messages;
+  }
+
+  const schemaAnalysis = directColumnSchemaShapes(parameter.schema);
+  messages.push(...schemaAnalysis.messages);
+  if (schemaAnalysis.messages.length) return messages;
+
+  const acceptsScalar = schemaAnalysis.shapes.has('scalar');
+  const acceptsList = schemaAnalysis.shapes.has('list');
+  const schemaCardinality = acceptsScalar && acceptsList
+    ? 'scalar_or_list'
+    : acceptsScalar
+      ? 'scalar'
+      : acceptsList
+        ? 'list'
+        : null;
+
+  if (schemaCardinality === null) {
+    messages.push(
+      'column_semantics requires schema to accept a string/integer column identifier or array',
+    );
+  } else if (semantics.cardinality !== schemaCardinality) {
+    messages.push(
+      `column_semantics.cardinality ${semantics.cardinality} does not match schema shape ${schemaCardinality}`,
+    );
+  }
+
+  return messages;
+}
+
 function validateTopLevel(metadata, source, entrySchema) {
   const allowed = new Set(Object.keys(entrySchema.properties));
   for (const required of entrySchema.required) {
@@ -571,6 +692,7 @@ function validateParameters(metadata, source) {
       'description',
       'required',
       'param_group',
+      'column_semantics',
       'runtime_default',
       'schema',
     ]);
@@ -606,6 +728,9 @@ function validateParameters(metadata, source) {
       fail(source, `${label}.param_group must be one of: ${PARAM_GROUP_ORDER.join(', ')}`);
     }
     validateSchemaFragment(parameter.schema, source, label);
+    for (const message of validateColumnSemantics(parameter)) {
+      fail(source, `${label}.${message}`);
+    }
   }
 }
 
@@ -1274,6 +1399,9 @@ function schemaAcceptsValue(schema, value) {
 function buildParameterSchema(parameter) {
   const result = JSON.parse(JSON.stringify(parameter.schema));
   result.description = parameter.description;
+  if (parameter.column_semantics) {
+    result['x-wrangles-column'] = JSON.parse(JSON.stringify(parameter.column_semantics));
+  }
   if (
     hasOwn(parameter, 'runtime_default') &&
     schemaAcceptsValue(parameter.schema, parameter.runtime_default)
@@ -2374,7 +2502,11 @@ async function main() {
   );
 }
 
-main().catch((error) => {
-  console.error(error.message);
-  process.exitCode = 1;
-});
+if (require.main === module) {
+  main().catch((error) => {
+    console.error(error.message);
+    process.exitCode = 1;
+  });
+}
+
+module.exports = {validateColumnSemantics};
diff --git a/wrangles-docs/scripts/compile-registry.test.cjs b/wrangles-docs/scripts/compile-registry.test.cjs
new file mode 100644
index 0000000..ea835cf
--- /dev/null
+++ b/wrangles-docs/scripts/compile-registry.test.cjs
@@ -0,0 +1,211 @@
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const test = require('node:test');
+
+const {validateColumnSemantics} = require('./compile-registry.cjs');
+
+const siteRoot = path.resolve(__dirname, '..');
+const repositoryRoot = path.resolve(siteRoot, '..');
+const contractsRoot = path.join(siteRoot, 'static', 'registry', 'contracts');
+const entrySchemaPath = path.join(
+  repositoryRoot,
+  'registry',
+  'schema',
+  'wrangle-entry.schema.json',
+);
+const recipeSchemaPath = path.join(
+  siteRoot,
+  'static',
+  'schemas',
+  'recipes',
+  'registry',
+  'schema.json',
+);
+const recipeWriterSchemaPath = path.join(
+  siteRoot,
+  'static',
+  'schemas',
+  'recipes',
+  'registry',
+  'recipe-writer.schema.json',
+);
+
+function parameterContract(relativeContract, parameterName) {
+  const contract = JSON.parse(
+    fs.readFileSync(path.join(contractsRoot, relativeContract), 'utf8'),
+  );
+  return contract.parameters.find((parameter) => parameter.name === parameterName);
+}
+
+test('column semantics are optional and accept every supported cardinality', () => {
+  assert.deepEqual(validateColumnSemantics({schema: {type: 'boolean'}}), []);
+
+  const validParameters = [
+    {
+      column_semantics: {role: 'reference', cardinality: 'scalar'},
+      schema: {type: ['string', 'null']},
+    },
+    {
+      column_semantics: {role: 'reference', cardinality: 'list'},
+      schema: {type: 'array', items: {type: ['string', 'integer']}},
+    },
+    {
+      column_semantics: {role: 'destination', cardinality: 'scalar_or_list'},
+      schema: {
+        type: ['string', 'integer', 'array', 'null'],
+        items: {type: ['string', 'integer']},
+      },
+    },
+  ];
+
+  for (const parameter of validParameters) {
+    assert.deepEqual(validateColumnSemantics(parameter), []);
+  }
+});
+
+test('column semantics reject unknown fields, invalid roles, and schema mismatches', () => {
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'source', cardinality: 'scalar', effect: 'add'},
+      schema: {type: ['string', 'array'], items: {type: 'string'}},
+    }),
+    [
+      'column_semantics has unknown field effect',
+      'column_semantics.role must be one of: reference, destination',
+      'column_semantics.cardinality scalar does not match schema shape scalar_or_list',
+    ],
+  );
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'destination', cardinality: 'scalar'},
+      schema: {type: 'boolean'},
+    }),
+    [
+      'schema accepts unsupported parameter value type boolean; object, mapping, nested-list, and other indirect locations require a future locator vocabulary',
+    ],
+  );
+});
+
+test('column semantics reject non-column branches and indirect identifier locations', () => {
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'destination', cardinality: 'scalar'},
+      schema: {type: ['string', 'object']},
+    }),
+    [
+      'schema accepts unsupported parameter value type object; object, mapping, nested-list, and other indirect locations require a future locator vocabulary',
+    ],
+  );
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'reference', cardinality: 'list'},
+      schema: {type: 'array'},
+    }),
+    ['schema array items must be explicitly limited to string/integer column identifiers'],
+  );
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'destination', cardinality: 'list'},
+      schema: {type: 'array', items: {type: 'object'}},
+    }),
+    [
+      'schema.items accepts unsupported array item type object; object, mapping, nested-list, and other indirect locations require a future locator vocabulary',
+    ],
+  );
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'reference', cardinality: 'scalar'},
+      schema: {$ref: '#/$defs/column'},
+    }),
+    ['schema uses $ref; indirect column locations require a future locator vocabulary'],
+  );
+  assert.deepEqual(
+    validateColumnSemantics({
+      column_semantics: {role: 'reference', cardinality: 'scalar'},
+      schema: {allOf: [{type: 'string'}]},
+    }),
+    ['schema uses allOf; indirect column locations require a future locator vocabulary'],
+  );
+});
+
+test('entry schema publishes the closed column semantics vocabulary', () => {
+  const entrySchema = JSON.parse(fs.readFileSync(entrySchemaPath, 'utf8'));
+  const columnSemantics = entrySchema.$defs.column_semantics;
+
+  assert.equal(columnSemantics.additionalProperties, false);
+  assert.deepEqual(columnSemantics.required, ['role', 'cardinality']);
+  assert.deepEqual(columnSemantics.properties.role.enum, ['reference', 'destination']);
+  assert.deepEqual(
+    columnSemantics.properties.cardinality.enum,
+    ['scalar', 'list', 'scalar_or_list'],
+  );
+  assert.deepEqual(
+    entrySchema.$defs.parameter.properties.column_semantics,
+    {$ref: '#/$defs/column_semantics'},
+  );
+});
+
+test('compiled contracts preserve representative column semantics', () => {
+  const cases = [
+    [
+      'standardize/clean.json',
+      'input',
+      {role: 'reference', cardinality: 'scalar_or_list'},
+    ],
+    [
+      'standardize/clean.json',
+      'output',
+      {role: 'destination', cardinality: 'scalar_or_list'},
+    ],
+    ['extract/date-range.json', 'start_time', {role: 'reference', cardinality: 'scalar'}],
+    ['extract/date-range.json', 'end_time', {role: 'reference', cardinality: 'scalar'}],
+    ['extract/date-range.json', 'output', {role: 'destination', cardinality: 'scalar'}],
+    ['drop.json', 'columns', {role: 'reference', cardinality: 'scalar_or_list'}],
+    ['rename.json', 'input', {role: 'reference', cardinality: 'scalar_or_list'}],
+    ['rename.json', 'output', {role: 'destination', cardinality: 'scalar_or_list'}],
+  ];
+
+  for (const [contract, parameterName, expected] of cases) {
+    assert.deepEqual(parameterContract(contract, parameterName).column_semantics, expected);
+  }
+
+  for (const [contract, parameterName] of [
+    ['create/column.json', 'output'],
+    ['create/embeddings.json', 'input'],
+    ['create/embeddings.json', 'output'],
+    ['merge/coalesce.json', 'input'],
+    ['merge/coalesce.json', 'output'],
+  ]) {
+    assert.equal(parameterContract(contract, parameterName).column_semantics, undefined);
+  }
+});
+
+test('recipe schema exposes column semantics as JSON Schema annotations', () => {
+  const schemas = [recipeSchemaPath, recipeWriterSchemaPath].map((filename) =>
+    JSON.parse(fs.readFileSync(filename, 'utf8')),
+  );
+
+  for (const schema of schemas) {
+    const wrangles = schema.$defs.wrangles.items.properties;
+    assert.deepEqual(
+      wrangles['standardize.clean'].properties.input['x-wrangles-column'],
+      {role: 'reference', cardinality: 'scalar_or_list'},
+    );
+    assert.deepEqual(wrangles.drop.properties.columns['x-wrangles-column'], {
+      role: 'reference',
+      cardinality: 'scalar_or_list',
+    });
+    assert.deepEqual(
+      wrangles['extract.date_range'].properties.start_time['x-wrangles-column'],
+      {role: 'reference', cardinality: 'scalar'},
+    );
+    assert.deepEqual(
+      wrangles['extract.date_range'].properties.output['x-wrangles-column'],
+      {role: 'destination', cardinality: 'scalar'},
+    );
+    assert.equal(wrangles['create.column'].properties.output['x-wrangles-column'], undefined);
+    assert.equal(wrangles['create.embeddings'].properties.input['x-wrangles-column'], undefined);
+    assert.equal(wrangles['merge.coalesce'].properties.input['x-wrangles-column'], undefined);
+  }
+});
diff --git a/wrangles-docs/static/registry/contracts/accordion.json b/wrangles-docs/static/registry/contracts/accordion.json
index 081b2d2..28354df 100644
--- a/wrangles-docs/static/registry/contracts/accordion.json
+++ b/wrangles-docs/static/registry/contracts/accordion.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/batch.json b/wrangles-docs/static/registry/contracts/batch.json
index 4b859c7..0697d46 100644
--- a/wrangles-docs/static/registry/contracts/batch.json
+++ b/wrangles-docs/static/registry/contracts/batch.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/classify.json b/wrangles-docs/static/registry/contracts/classify.json
index b941a09..c9df6a7 100644
--- a/wrangles-docs/static/registry/contracts/classify.json
+++ b/wrangles-docs/static/registry/contracts/classify.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "06669ef8-cdd1-42f7-8078-98e0b7a42c30",
diff --git a/wrangles-docs/static/registry/contracts/clean-whitespaces.json b/wrangles-docs/static/registry/contracts/clean-whitespaces.json
index 9e71ef1..70c6361 100644
--- a/wrangles-docs/static/registry/contracts/clean-whitespaces.json
+++ b/wrangles-docs/static/registry/contracts/clean-whitespaces.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "e36e15c4-f0ad-43f8-8555-ef683a8ab892",
diff --git a/wrangles-docs/static/registry/contracts/compare/lists.json b/wrangles-docs/static/registry/contracts/compare/lists.json
index b3f9202..04221e1 100644
--- a/wrangles-docs/static/registry/contracts/compare/lists.json
+++ b/wrangles-docs/static/registry/contracts/compare/lists.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "a393225e-7ccf-4708-83f8-d5abd6ba9b1e",
diff --git a/wrangles-docs/static/registry/contracts/compare/text.json b/wrangles-docs/static/registry/contracts/compare/text.json
index ff05db9..c250fd3 100644
--- a/wrangles-docs/static/registry/contracts/compare/text.json
+++ b/wrangles-docs/static/registry/contracts/compare/text.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "31905b74-ce58-45cd-8add-821cc04ab946",
diff --git a/wrangles-docs/static/registry/contracts/compute/case-when.json b/wrangles-docs/static/registry/contracts/compute/case-when.json
index 728d3b0..74e09d1 100644
--- a/wrangles-docs/static/registry/contracts/compute/case-when.json
+++ b/wrangles-docs/static/registry/contracts/compute/case-when.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "9a9662e4-53d1-4932-8adf-bc3e7aa364ad",
diff --git a/wrangles-docs/static/registry/contracts/compute/score-search-results.json b/wrangles-docs/static/registry/contracts/compute/score-search-results.json
index 2308a5d..e23fd0b 100644
--- a/wrangles-docs/static/registry/contracts/compute/score-search-results.json
+++ b/wrangles-docs/static/registry/contracts/compute/score-search-results.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "313a8ec0-cf13-4956-8d3b-5362b8641d0f",
diff --git a/wrangles-docs/static/registry/contracts/concurrent.json b/wrangles-docs/static/registry/contracts/concurrent.json
index 4cb2c18..b59e93a 100644
--- a/wrangles-docs/static/registry/contracts/concurrent.json
+++ b/wrangles-docs/static/registry/contracts/concurrent.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/convert/case.json b/wrangles-docs/static/registry/contracts/convert/case.json
index 77e2cc5..53d7209 100644
--- a/wrangles-docs/static/registry/contracts/convert/case.json
+++ b/wrangles-docs/static/registry/contracts/convert/case.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "12ff4120-3613-4801-8653-99c793477fbc",
diff --git a/wrangles-docs/static/registry/contracts/convert/data-type.json b/wrangles-docs/static/registry/contracts/convert/data-type.json
index 44cf1c6..f5baf27 100644
--- a/wrangles-docs/static/registry/contracts/convert/data-type.json
+++ b/wrangles-docs/static/registry/contracts/convert/data-type.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "52384f01-7164-404f-8615-063e7677a588",
diff --git a/wrangles-docs/static/registry/contracts/convert/fraction-to-decimal.json b/wrangles-docs/static/registry/contracts/convert/fraction-to-decimal.json
index c3b37f1..ee084d2 100644
--- a/wrangles-docs/static/registry/contracts/convert/fraction-to-decimal.json
+++ b/wrangles-docs/static/registry/contracts/convert/fraction-to-decimal.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "7c55752e-70ab-4809-8298-c59436127457",
diff --git a/wrangles-docs/static/registry/contracts/convert/from-json.json b/wrangles-docs/static/registry/contracts/convert/from-json.json
index 6e7c4d9..a174368 100644
--- a/wrangles-docs/static/registry/contracts/convert/from-json.json
+++ b/wrangles-docs/static/registry/contracts/convert/from-json.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "e370dfcf-b0fe-4c48-8a52-6f34c47e7978",
diff --git a/wrangles-docs/static/registry/contracts/convert/from-yaml.json b/wrangles-docs/static/registry/contracts/convert/from-yaml.json
index f93cd82..299b8bd 100644
--- a/wrangles-docs/static/registry/contracts/convert/from-yaml.json
+++ b/wrangles-docs/static/registry/contracts/convert/from-yaml.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "b1c20004-5f80-41c2-84d2-2d4601a033b5",
diff --git a/wrangles-docs/static/registry/contracts/convert/to-json.json b/wrangles-docs/static/registry/contracts/convert/to-json.json
index bce6fef..6f5f4b0 100644
--- a/wrangles-docs/static/registry/contracts/convert/to-json.json
+++ b/wrangles-docs/static/registry/contracts/convert/to-json.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "94e54eb7-2b8c-4047-89d0-fb5d16baf396",
diff --git a/wrangles-docs/static/registry/contracts/convert/to-yaml.json b/wrangles-docs/static/registry/contracts/convert/to-yaml.json
index 4d0eea8..c2132fc 100644
--- a/wrangles-docs/static/registry/contracts/convert/to-yaml.json
+++ b/wrangles-docs/static/registry/contracts/convert/to-yaml.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "4cd6252f-ce47-4a9d-8272-3d87e875b72a",
diff --git a/wrangles-docs/static/registry/contracts/copy.json b/wrangles-docs/static/registry/contracts/copy.json
index f3c8b6e..d1a701b 100644
--- a/wrangles-docs/static/registry/contracts/copy.json
+++ b/wrangles-docs/static/registry/contracts/copy.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "b002fbdc-92c0-4347-889d-0f4bfeec99fa",
diff --git a/wrangles-docs/static/registry/contracts/create/bins.json b/wrangles-docs/static/registry/contracts/create/bins.json
index 1c8755d..fa9a843 100644
--- a/wrangles-docs/static/registry/contracts/create/bins.json
+++ b/wrangles-docs/static/registry/contracts/create/bins.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "232e3ba0-4735-4934-88aa-0163181abb3f",
diff --git a/wrangles-docs/static/registry/contracts/create/column.json b/wrangles-docs/static/registry/contracts/create/column.json
index 22350ad..8e7207f 100644
--- a/wrangles-docs/static/registry/contracts/create/column.json
+++ b/wrangles-docs/static/registry/contracts/create/column.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "5a18e2c8-ec7c-45f5-88fd-bb5c358a8b40",
diff --git a/wrangles-docs/static/registry/contracts/create/embeddings.json b/wrangles-docs/static/registry/contracts/create/embeddings.json
index dc576ca..b4bb3e5 100644
--- a/wrangles-docs/static/registry/contracts/create/embeddings.json
+++ b/wrangles-docs/static/registry/contracts/create/embeddings.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "e3518afd-a819-40ec-8b49-eb25690220c1",
diff --git a/wrangles-docs/static/registry/contracts/create/guid.json b/wrangles-docs/static/registry/contracts/create/guid.json
index ab9102d..d553c19 100644
--- a/wrangles-docs/static/registry/contracts/create/guid.json
+++ b/wrangles-docs/static/registry/contracts/create/guid.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "cf3aaab2-3d5b-4c9b-826e-7af7510521c9",
diff --git a/wrangles-docs/static/registry/contracts/create/hash.json b/wrangles-docs/static/registry/contracts/create/hash.json
index 730bcc1..cd94dc3 100644
--- a/wrangles-docs/static/registry/contracts/create/hash.json
+++ b/wrangles-docs/static/registry/contracts/create/hash.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "11e8fc13-00d2-4779-8d87-6288b07de7e7",
diff --git a/wrangles-docs/static/registry/contracts/create/index.json b/wrangles-docs/static/registry/contracts/create/index.json
index 1a4fee3..6db1397 100644
--- a/wrangles-docs/static/registry/contracts/create/index.json
+++ b/wrangles-docs/static/registry/contracts/create/index.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "0a4909ca-6e14-4da7-8a70-a7fd106d6944",
diff --git a/wrangles-docs/static/registry/contracts/create/jinja.json b/wrangles-docs/static/registry/contracts/create/jinja.json
index a6fe69a..2096bbc 100644
--- a/wrangles-docs/static/registry/contracts/create/jinja.json
+++ b/wrangles-docs/static/registry/contracts/create/jinja.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "10fc6709-16d4-4eab-8f56-6cb5d170ea66",
diff --git a/wrangles-docs/static/registry/contracts/create/uuid.json b/wrangles-docs/static/registry/contracts/create/uuid.json
index 943489a..7fe94e7 100644
--- a/wrangles-docs/static/registry/contracts/create/uuid.json
+++ b/wrangles-docs/static/registry/contracts/create/uuid.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "c376f3ff-2283-4c4c-8d7f-70db6f53ed19",
diff --git a/wrangles-docs/static/registry/contracts/date-calculator.json b/wrangles-docs/static/registry/contracts/date-calculator.json
index 0877809..a733588 100644
--- a/wrangles-docs/static/registry/contracts/date-calculator.json
+++ b/wrangles-docs/static/registry/contracts/date-calculator.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "19cfeb4f-02af-4ab2-895c-0ff2bb5cce19",
diff --git a/wrangles-docs/static/registry/contracts/drop.json b/wrangles-docs/static/registry/contracts/drop.json
index b1f7835..d6c6de6 100644
--- a/wrangles-docs/static/registry/contracts/drop.json
+++ b/wrangles-docs/static/registry/contracts/drop.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "363bffbf-397e-4975-8382-e9efa5e9eed6",
@@ -43,11 +43,18 @@
       "description": "Name of the column(s) to drop.",
       "required": true,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "reference",
+        "cardinality": "scalar_or_list"
+      },
       "schema": {
         "type": [
           "string",
           "array"
-        ]
+        ],
+        "items": {
+          "type": "string"
+        }
       }
     },
     {
diff --git a/wrangles-docs/static/registry/contracts/explode.json b/wrangles-docs/static/registry/contracts/explode.json
index be794d2..0159227 100644
--- a/wrangles-docs/static/registry/contracts/explode.json
+++ b/wrangles-docs/static/registry/contracts/explode.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "4e4b13ac-8d50-4b2c-85c8-2c31de1e817d",
diff --git a/wrangles-docs/static/registry/contracts/extract/address.json b/wrangles-docs/static/registry/contracts/extract/address.json
index 7d60cc7..b3d1534 100644
--- a/wrangles-docs/static/registry/contracts/extract/address.json
+++ b/wrangles-docs/static/registry/contracts/extract/address.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "44153f95-4581-4cee-898e-b3b4714045fd",
diff --git a/wrangles-docs/static/registry/contracts/extract/ai.json b/wrangles-docs/static/registry/contracts/extract/ai.json
index 69d7895..1876b7d 100644
--- a/wrangles-docs/static/registry/contracts/extract/ai.json
+++ b/wrangles-docs/static/registry/contracts/extract/ai.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "d9f89b00-fda3-4f4c-826c-6417b9390607",
diff --git a/wrangles-docs/static/registry/contracts/extract/attributes.json b/wrangles-docs/static/registry/contracts/extract/attributes.json
index c7e153a..25d166d 100644
--- a/wrangles-docs/static/registry/contracts/extract/attributes.json
+++ b/wrangles-docs/static/registry/contracts/extract/attributes.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "03ccedef-c938-41f1-8980-280f1a91542e",
diff --git a/wrangles-docs/static/registry/contracts/extract/brackets.json b/wrangles-docs/static/registry/contracts/extract/brackets.json
index 23e6a8b..8c895d6 100644
--- a/wrangles-docs/static/registry/contracts/extract/brackets.json
+++ b/wrangles-docs/static/registry/contracts/extract/brackets.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "9b4c15fa-2aaa-40c8-8834-6e835760bee5",
diff --git a/wrangles-docs/static/registry/contracts/extract/codes.json b/wrangles-docs/static/registry/contracts/extract/codes.json
index 908c977..3d699fc 100644
--- a/wrangles-docs/static/registry/contracts/extract/codes.json
+++ b/wrangles-docs/static/registry/contracts/extract/codes.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "da591387-0fca-4842-8bcb-d19f561f0292",
diff --git a/wrangles-docs/static/registry/contracts/extract/custom.json b/wrangles-docs/static/registry/contracts/extract/custom.json
index fb3b441..346e9cd 100644
--- a/wrangles-docs/static/registry/contracts/extract/custom.json
+++ b/wrangles-docs/static/registry/contracts/extract/custom.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "e8e96b76-86bf-41dc-8d16-825dcff9688b",
diff --git a/wrangles-docs/static/registry/contracts/extract/date-properties.json b/wrangles-docs/static/registry/contracts/extract/date-properties.json
index 1e29bf3..1ea73c7 100644
--- a/wrangles-docs/static/registry/contracts/extract/date-properties.json
+++ b/wrangles-docs/static/registry/contracts/extract/date-properties.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "a346de62-93cd-44ba-8d30-a6305629c6d7",
diff --git a/wrangles-docs/static/registry/contracts/extract/date-range.json b/wrangles-docs/static/registry/contracts/extract/date-range.json
index 935d468..f3ba94f 100644
--- a/wrangles-docs/static/registry/contracts/extract/date-range.json
+++ b/wrangles-docs/static/registry/contracts/extract/date-range.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "9cebfa6f-a524-4aec-84a7-02d77b792843",
@@ -43,6 +43,10 @@
       "description": "Name of the start date column.",
       "required": true,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "reference",
+        "cardinality": "scalar"
+      },
       "schema": {
         "type": "string"
       }
@@ -52,6 +56,10 @@
       "description": "Name of the end date column.",
       "required": true,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "reference",
+        "cardinality": "scalar"
+      },
       "schema": {
         "type": "string"
       }
@@ -61,6 +69,10 @@
       "description": "Name of the output column.",
       "required": true,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "destination",
+        "cardinality": "scalar"
+      },
       "schema": {
         "type": "string"
       }
diff --git a/wrangles-docs/static/registry/contracts/extract/html.json b/wrangles-docs/static/registry/contracts/extract/html.json
index f85cb39..5c1c0c8 100644
--- a/wrangles-docs/static/registry/contracts/extract/html.json
+++ b/wrangles-docs/static/registry/contracts/extract/html.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "728fc87a-a20d-4efa-833a-612e0b5eadc3",
diff --git a/wrangles-docs/static/registry/contracts/extract/properties.json b/wrangles-docs/static/registry/contracts/extract/properties.json
index 55813d4..7efa2f1 100644
--- a/wrangles-docs/static/registry/contracts/extract/properties.json
+++ b/wrangles-docs/static/registry/contracts/extract/properties.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "23bbdb86-fd13-4b78-8fff-a7a76769ab63",
diff --git a/wrangles-docs/static/registry/contracts/extract/regex.json b/wrangles-docs/static/registry/contracts/extract/regex.json
index b9aedd1..23f3173 100644
--- a/wrangles-docs/static/registry/contracts/extract/regex.json
+++ b/wrangles-docs/static/registry/contracts/extract/regex.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "9aa0253a-4b70-4737-832c-964e15967289",
diff --git a/wrangles-docs/static/registry/contracts/filter.json b/wrangles-docs/static/registry/contracts/filter.json
index b2c62cb..a1199bf 100644
--- a/wrangles-docs/static/registry/contracts/filter.json
+++ b/wrangles-docs/static/registry/contracts/filter.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "e3242acf-d204-433f-8373-205b77481131",
diff --git a/wrangles-docs/static/registry/contracts/format/dates.json b/wrangles-docs/static/registry/contracts/format/dates.json
index b52a3e4..501da3f 100644
--- a/wrangles-docs/static/registry/contracts/format/dates.json
+++ b/wrangles-docs/static/registry/contracts/format/dates.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "a3c15135-4f7a-4659-83fd-f657afa603c9",
diff --git a/wrangles-docs/static/registry/contracts/format/pad.json b/wrangles-docs/static/registry/contracts/format/pad.json
index 0e39991..47895bd 100644
--- a/wrangles-docs/static/registry/contracts/format/pad.json
+++ b/wrangles-docs/static/registry/contracts/format/pad.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "76c19378-38f4-45aa-85d1-3cdf8f8aae29",
diff --git a/wrangles-docs/static/registry/contracts/format/prefix.json b/wrangles-docs/static/registry/contracts/format/prefix.json
index 93654c4..e926adf 100644
--- a/wrangles-docs/static/registry/contracts/format/prefix.json
+++ b/wrangles-docs/static/registry/contracts/format/prefix.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "c12f99b9-2363-4da7-8405-7c73b87906e5",
diff --git a/wrangles-docs/static/registry/contracts/format/price-breaks.json b/wrangles-docs/static/registry/contracts/format/price-breaks.json
index b5d331d..59c28b4 100644
--- a/wrangles-docs/static/registry/contracts/format/price-breaks.json
+++ b/wrangles-docs/static/registry/contracts/format/price-breaks.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/format/remove-duplicates.json b/wrangles-docs/static/registry/contracts/format/remove-duplicates.json
index 0711561..cccd09b 100644
--- a/wrangles-docs/static/registry/contracts/format/remove-duplicates.json
+++ b/wrangles-docs/static/registry/contracts/format/remove-duplicates.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "283b9e78-b2b2-43d0-844f-9842c33120aa",
diff --git a/wrangles-docs/static/registry/contracts/format/significant-figures.json b/wrangles-docs/static/registry/contracts/format/significant-figures.json
index e8db779..5dae3d4 100644
--- a/wrangles-docs/static/registry/contracts/format/significant-figures.json
+++ b/wrangles-docs/static/registry/contracts/format/significant-figures.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "a359f72a-5250-4dd8-84f6-8a8173bee0f6",
diff --git a/wrangles-docs/static/registry/contracts/format/suffix.json b/wrangles-docs/static/registry/contracts/format/suffix.json
index 824deff..0beef98 100644
--- a/wrangles-docs/static/registry/contracts/format/suffix.json
+++ b/wrangles-docs/static/registry/contracts/format/suffix.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "8d127060-ba2d-4934-897f-07662e01e40b",
diff --git a/wrangles-docs/static/registry/contracts/format/trim.json b/wrangles-docs/static/registry/contracts/format/trim.json
index 540a3c6..34fcc74 100644
--- a/wrangles-docs/static/registry/contracts/format/trim.json
+++ b/wrangles-docs/static/registry/contracts/format/trim.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "af16b3c1-c230-4868-8ebe-f574904a0c76",
diff --git a/wrangles-docs/static/registry/contracts/generate/ai.json b/wrangles-docs/static/registry/contracts/generate/ai.json
index ee51caf..f66dc0d 100644
--- a/wrangles-docs/static/registry/contracts/generate/ai.json
+++ b/wrangles-docs/static/registry/contracts/generate/ai.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "12c31c6c-cade-484d-84ba-7f302bf6af52",
diff --git a/wrangles-docs/static/registry/contracts/huggingface.json b/wrangles-docs/static/registry/contracts/huggingface.json
index 6f12e80..d8927a2 100644
--- a/wrangles-docs/static/registry/contracts/huggingface.json
+++ b/wrangles-docs/static/registry/contracts/huggingface.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "ae12cf20-4934-428f-84a9-a6898cb7ffe0",
diff --git a/wrangles-docs/static/registry/contracts/log.json b/wrangles-docs/static/registry/contracts/log.json
index 1dfee03..3078e54 100644
--- a/wrangles-docs/static/registry/contracts/log.json
+++ b/wrangles-docs/static/registry/contracts/log.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "6177808e-aa2d-4d0b-8385-858b16948a5d",
diff --git a/wrangles-docs/static/registry/contracts/lookup.json b/wrangles-docs/static/registry/contracts/lookup.json
index 615c63e..8ab8c4a 100644
--- a/wrangles-docs/static/registry/contracts/lookup.json
+++ b/wrangles-docs/static/registry/contracts/lookup.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "b3339193-d1cc-4c89-8ed6-901efa6d81be",
diff --git a/wrangles-docs/static/registry/contracts/math.json b/wrangles-docs/static/registry/contracts/math.json
index d7fb938..589dde5 100644
--- a/wrangles-docs/static/registry/contracts/math.json
+++ b/wrangles-docs/static/registry/contracts/math.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "494b11ad-00c1-4748-8b93-6bec982f4fec",
diff --git a/wrangles-docs/static/registry/contracts/maths.json b/wrangles-docs/static/registry/contracts/maths.json
index abba552..22582d4 100644
--- a/wrangles-docs/static/registry/contracts/maths.json
+++ b/wrangles-docs/static/registry/contracts/maths.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/matrix.json b/wrangles-docs/static/registry/contracts/matrix.json
index 0fc8318..eb27614 100644
--- a/wrangles-docs/static/registry/contracts/matrix.json
+++ b/wrangles-docs/static/registry/contracts/matrix.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/merge/coalesce.json b/wrangles-docs/static/registry/contracts/merge/coalesce.json
index 1725244..0ecdc36 100644
--- a/wrangles-docs/static/registry/contracts/merge/coalesce.json
+++ b/wrangles-docs/static/registry/contracts/merge/coalesce.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "25c1a60d-fa48-4b9a-8c03-0921d5b31049",
diff --git a/wrangles-docs/static/registry/contracts/merge/concatenate.json b/wrangles-docs/static/registry/contracts/merge/concatenate.json
index 922a82b..5b0ee0a 100644
--- a/wrangles-docs/static/registry/contracts/merge/concatenate.json
+++ b/wrangles-docs/static/registry/contracts/merge/concatenate.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "6ff76728-e1f6-4d3d-8946-6aa3b7524b3f",
diff --git a/wrangles-docs/static/registry/contracts/merge/dictionaries.json b/wrangles-docs/static/registry/contracts/merge/dictionaries.json
index 2a90303..285d8d9 100644
--- a/wrangles-docs/static/registry/contracts/merge/dictionaries.json
+++ b/wrangles-docs/static/registry/contracts/merge/dictionaries.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "93e27737-e966-4ba9-8777-4e96724ebfc4",
diff --git a/wrangles-docs/static/registry/contracts/merge/key-value-pairs.json b/wrangles-docs/static/registry/contracts/merge/key-value-pairs.json
index ae7ffcb..8e3cebe 100644
--- a/wrangles-docs/static/registry/contracts/merge/key-value-pairs.json
+++ b/wrangles-docs/static/registry/contracts/merge/key-value-pairs.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "8a2cd37c-8ef7-4b05-8264-36512f5dd837",
diff --git a/wrangles-docs/static/registry/contracts/merge/lists.json b/wrangles-docs/static/registry/contracts/merge/lists.json
index 7104aea..d28ba74 100644
--- a/wrangles-docs/static/registry/contracts/merge/lists.json
+++ b/wrangles-docs/static/registry/contracts/merge/lists.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "d9978f00-b3d4-4583-884e-a53b98a43e9a",
diff --git a/wrangles-docs/static/registry/contracts/merge/to-dict.json b/wrangles-docs/static/registry/contracts/merge/to-dict.json
index ab26408..e9ee4cd 100644
--- a/wrangles-docs/static/registry/contracts/merge/to-dict.json
+++ b/wrangles-docs/static/registry/contracts/merge/to-dict.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "9b869210-0d89-403b-8409-7cecdb5f9c7c",
diff --git a/wrangles-docs/static/registry/contracts/merge/to-list.json b/wrangles-docs/static/registry/contracts/merge/to-list.json
index e3c5b88..3baadd8 100644
--- a/wrangles-docs/static/registry/contracts/merge/to-list.json
+++ b/wrangles-docs/static/registry/contracts/merge/to-list.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "d5300fe7-c8a4-4a41-8f12-f2c1698678cc",
diff --git a/wrangles-docs/static/registry/contracts/python.json b/wrangles-docs/static/registry/contracts/python.json
index f268f69..42146ad 100644
--- a/wrangles-docs/static/registry/contracts/python.json
+++ b/wrangles-docs/static/registry/contracts/python.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "c0398a11-7731-4e47-8df0-b07eea0b1d6c",
diff --git a/wrangles-docs/static/registry/contracts/recipe.json b/wrangles-docs/static/registry/contracts/recipe.json
index ea0e4e2..5663ac9 100644
--- a/wrangles-docs/static/registry/contracts/recipe.json
+++ b/wrangles-docs/static/registry/contracts/recipe.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/reindex.json b/wrangles-docs/static/registry/contracts/reindex.json
index 5fa9cc1..bf2ea4f 100644
--- a/wrangles-docs/static/registry/contracts/reindex.json
+++ b/wrangles-docs/static/registry/contracts/reindex.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "def87df8-72da-4e34-83c1-1fde25126257",
diff --git a/wrangles-docs/static/registry/contracts/remove-words.json b/wrangles-docs/static/registry/contracts/remove-words.json
index f6797a0..3bfd977 100644
--- a/wrangles-docs/static/registry/contracts/remove-words.json
+++ b/wrangles-docs/static/registry/contracts/remove-words.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "543b96c3-f354-48be-8046-bf0cb9fbaf56",
diff --git a/wrangles-docs/static/registry/contracts/rename.json b/wrangles-docs/static/registry/contracts/rename.json
index 074253e..4f43736 100644
--- a/wrangles-docs/static/registry/contracts/rename.json
+++ b/wrangles-docs/static/registry/contracts/rename.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "ab06898f-faf7-42e7-8275-5e3034a4d727",
@@ -44,6 +44,10 @@
       "description": "Name or list of input columns.",
       "required": false,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "reference",
+        "cardinality": "scalar_or_list"
+      },
       "runtime_default": null,
       "schema": {
         "type": [
@@ -51,7 +55,13 @@
           "integer",
           "array",
           "null"
-        ]
+        ],
+        "items": {
+          "type": [
+            "string",
+            "integer"
+          ]
+        }
       }
     },
     {
@@ -59,13 +69,20 @@
       "description": "Name or list of output columns.",
       "required": false,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "destination",
+        "cardinality": "scalar_or_list"
+      },
       "runtime_default": null,
       "schema": {
         "type": [
           "string",
           "array",
           "null"
-        ]
+        ],
+        "items": {
+          "type": "string"
+        }
       }
     },
     {
diff --git a/wrangles-docs/static/registry/contracts/replace.json b/wrangles-docs/static/registry/contracts/replace.json
index 88fb0d3..0e70ead 100644
--- a/wrangles-docs/static/registry/contracts/replace.json
+++ b/wrangles-docs/static/registry/contracts/replace.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "f0ab715e-9e0e-4614-83e4-5cd8ea08a09f",
diff --git a/wrangles-docs/static/registry/contracts/round.json b/wrangles-docs/static/registry/contracts/round.json
index 476c4c4..12c73d6 100644
--- a/wrangles-docs/static/registry/contracts/round.json
+++ b/wrangles-docs/static/registry/contracts/round.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "12f3111b-8511-4e42-8d3f-b5302dc3b4e4",
diff --git a/wrangles-docs/static/registry/contracts/search/find-links.json b/wrangles-docs/static/registry/contracts/search/find-links.json
index 4365e02..d04e73f 100644
--- a/wrangles-docs/static/registry/contracts/search/find-links.json
+++ b/wrangles-docs/static/registry/contracts/search/find-links.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "ec1f661b-2cbc-4a47-88e3-646179104376",
diff --git a/wrangles-docs/static/registry/contracts/search/retrieve-link-content.json b/wrangles-docs/static/registry/contracts/search/retrieve-link-content.json
index 7542fab..db916a6 100644
--- a/wrangles-docs/static/registry/contracts/search/retrieve-link-content.json
+++ b/wrangles-docs/static/registry/contracts/search/retrieve-link-content.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "3d5faa87-9e96-48c0-8226-5ae566e8d76c",
diff --git a/wrangles-docs/static/registry/contracts/select/columns.json b/wrangles-docs/static/registry/contracts/select/columns.json
index e0d2c80..543187d 100644
--- a/wrangles-docs/static/registry/contracts/select/columns.json
+++ b/wrangles-docs/static/registry/contracts/select/columns.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "bca12c60-3957-4dc5-83f7-5ee460df2a11",
diff --git a/wrangles-docs/static/registry/contracts/select/dictionary-element.json b/wrangles-docs/static/registry/contracts/select/dictionary-element.json
index e483efa..c320d50 100644
--- a/wrangles-docs/static/registry/contracts/select/dictionary-element.json
+++ b/wrangles-docs/static/registry/contracts/select/dictionary-element.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "5adaeada-6da8-464f-84cb-9fb5ecc17e48",
diff --git a/wrangles-docs/static/registry/contracts/select/element.json b/wrangles-docs/static/registry/contracts/select/element.json
index 9da8827..c7fa729 100644
--- a/wrangles-docs/static/registry/contracts/select/element.json
+++ b/wrangles-docs/static/registry/contracts/select/element.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "223d2f4e-3247-4189-8b6c-e73fe44c4266",
diff --git a/wrangles-docs/static/registry/contracts/select/group-by.json b/wrangles-docs/static/registry/contracts/select/group-by.json
index 36e51cd..3ded7d8 100644
--- a/wrangles-docs/static/registry/contracts/select/group-by.json
+++ b/wrangles-docs/static/registry/contracts/select/group-by.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "c0af10b1-423a-416c-8cb5-7e7fe1164964",
diff --git a/wrangles-docs/static/registry/contracts/select/head.json b/wrangles-docs/static/registry/contracts/select/head.json
index 41da2f6..2a497b4 100644
--- a/wrangles-docs/static/registry/contracts/select/head.json
+++ b/wrangles-docs/static/registry/contracts/select/head.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "237af1ec-db7d-415a-88b7-70586a2191fb",
diff --git a/wrangles-docs/static/registry/contracts/select/highest-confidence.json b/wrangles-docs/static/registry/contracts/select/highest-confidence.json
index 622635c..3395ed4 100644
--- a/wrangles-docs/static/registry/contracts/select/highest-confidence.json
+++ b/wrangles-docs/static/registry/contracts/select/highest-confidence.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "00aad85d-8cc8-42e5-86f3-e4ff916e8ac2",
diff --git a/wrangles-docs/static/registry/contracts/select/left.json b/wrangles-docs/static/registry/contracts/select/left.json
index 0a6df0b..d864d99 100644
--- a/wrangles-docs/static/registry/contracts/select/left.json
+++ b/wrangles-docs/static/registry/contracts/select/left.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "5cdd9857-0c77-43bf-80d7-d0a8cb6f980b",
diff --git a/wrangles-docs/static/registry/contracts/select/length.json b/wrangles-docs/static/registry/contracts/select/length.json
index a9a8ea2..4596a0d 100644
--- a/wrangles-docs/static/registry/contracts/select/length.json
+++ b/wrangles-docs/static/registry/contracts/select/length.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "4d7a5f66-0a4a-40e0-8298-d5c55754423d",
diff --git a/wrangles-docs/static/registry/contracts/select/list-element.json b/wrangles-docs/static/registry/contracts/select/list-element.json
index 8df21b1..0eb2b46 100644
--- a/wrangles-docs/static/registry/contracts/select/list-element.json
+++ b/wrangles-docs/static/registry/contracts/select/list-element.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "ec40495d-d29a-4f62-86dd-eafa43cf388a",
diff --git a/wrangles-docs/static/registry/contracts/select/right.json b/wrangles-docs/static/registry/contracts/select/right.json
index f8cb6c2..cdc0838 100644
--- a/wrangles-docs/static/registry/contracts/select/right.json
+++ b/wrangles-docs/static/registry/contracts/select/right.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "89ee82ec-3bc5-4bfa-899b-7a1260ef9bdb",
diff --git a/wrangles-docs/static/registry/contracts/select/sample.json b/wrangles-docs/static/registry/contracts/select/sample.json
index e866934..9e50538 100644
--- a/wrangles-docs/static/registry/contracts/select/sample.json
+++ b/wrangles-docs/static/registry/contracts/select/sample.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "95a84ab6-a66e-450f-8a4a-7a87e3a77932",
diff --git a/wrangles-docs/static/registry/contracts/select/substring.json b/wrangles-docs/static/registry/contracts/select/substring.json
index 73d32b7..ba84e68 100644
--- a/wrangles-docs/static/registry/contracts/select/substring.json
+++ b/wrangles-docs/static/registry/contracts/select/substring.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "8befddf8-602e-4fa9-8f16-4c547210ebec",
diff --git a/wrangles-docs/static/registry/contracts/select/tail.json b/wrangles-docs/static/registry/contracts/select/tail.json
index 9897cc2..2ab6c56 100644
--- a/wrangles-docs/static/registry/contracts/select/tail.json
+++ b/wrangles-docs/static/registry/contracts/select/tail.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "60853759-c160-49a4-87eb-036516a9d823",
diff --git a/wrangles-docs/static/registry/contracts/select/threshold.json b/wrangles-docs/static/registry/contracts/select/threshold.json
index 7cd2a28..2ee8d59 100644
--- a/wrangles-docs/static/registry/contracts/select/threshold.json
+++ b/wrangles-docs/static/registry/contracts/select/threshold.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "af2a5dcc-0ec0-48d7-8fb4-f58d9c5391d2",
diff --git a/wrangles-docs/static/registry/contracts/similarity.json b/wrangles-docs/static/registry/contracts/similarity.json
index 29eb36f..b4098ec 100644
--- a/wrangles-docs/static/registry/contracts/similarity.json
+++ b/wrangles-docs/static/registry/contracts/similarity.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "7c733344-4cce-4938-8013-53742fb46a90",
diff --git a/wrangles-docs/static/registry/contracts/sort.json b/wrangles-docs/static/registry/contracts/sort.json
index 169960c..b19d2c0 100644
--- a/wrangles-docs/static/registry/contracts/sort.json
+++ b/wrangles-docs/static/registry/contracts/sort.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "1dcf06ad-898a-4d83-862c-4774be37a687",
diff --git a/wrangles-docs/static/registry/contracts/split/dictionary.json b/wrangles-docs/static/registry/contracts/split/dictionary.json
index 0534f49..8cb040a 100644
--- a/wrangles-docs/static/registry/contracts/split/dictionary.json
+++ b/wrangles-docs/static/registry/contracts/split/dictionary.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "06ca98e4-d026-43f7-84eb-af246d401ba9",
diff --git a/wrangles-docs/static/registry/contracts/split/list.json b/wrangles-docs/static/registry/contracts/split/list.json
index dadc448..d1d575c 100644
--- a/wrangles-docs/static/registry/contracts/split/list.json
+++ b/wrangles-docs/static/registry/contracts/split/list.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "3260b9f7-aae2-499f-8004-d211c2cf643e",
diff --git a/wrangles-docs/static/registry/contracts/split/text.json b/wrangles-docs/static/registry/contracts/split/text.json
index a4d1dce..700d6e4 100644
--- a/wrangles-docs/static/registry/contracts/split/text.json
+++ b/wrangles-docs/static/registry/contracts/split/text.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "e76e43f7-d129-4bf8-87b4-a304a378b130",
diff --git a/wrangles-docs/static/registry/contracts/split/tokenize.json b/wrangles-docs/static/registry/contracts/split/tokenize.json
index 2189c3b..2df9bf2 100644
--- a/wrangles-docs/static/registry/contracts/split/tokenize.json
+++ b/wrangles-docs/static/registry/contracts/split/tokenize.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "6cc88418-ae0c-43f6-84ee-31e0d5f838c3",
diff --git a/wrangles-docs/static/registry/contracts/sql.json b/wrangles-docs/static/registry/contracts/sql.json
index 00e1e55..b59b0c8 100644
--- a/wrangles-docs/static/registry/contracts/sql.json
+++ b/wrangles-docs/static/registry/contracts/sql.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "467a06b1-a697-4d31-8061-7d83a719fd79",
diff --git a/wrangles-docs/static/registry/contracts/standardize.json b/wrangles-docs/static/registry/contracts/standardize.json
index 7bd7af6..474838a 100644
--- a/wrangles-docs/static/registry/contracts/standardize.json
+++ b/wrangles-docs/static/registry/contracts/standardize.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "53cd3fdd-24e2-4411-8655-6014b92a3f3a",
diff --git a/wrangles-docs/static/registry/contracts/standardize/clean.json b/wrangles-docs/static/registry/contracts/standardize/clean.json
index f125f56..664f391 100644
--- a/wrangles-docs/static/registry/contracts/standardize/clean.json
+++ b/wrangles-docs/static/registry/contracts/standardize/clean.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
@@ -43,12 +43,22 @@
       "description": "Name or list of input columns.",
       "required": true,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "reference",
+        "cardinality": "scalar_or_list"
+      },
       "schema": {
         "type": [
           "string",
           "integer",
           "array"
-        ]
+        ],
+        "items": {
+          "type": [
+            "string",
+            "integer"
+          ]
+        }
       }
     },
     {
@@ -56,6 +66,10 @@
       "description": "Name or list of output columns. Defaults to overwriting input.",
       "required": false,
       "param_group": "I/O",
+      "column_semantics": {
+        "role": "destination",
+        "cardinality": "scalar_or_list"
+      },
       "runtime_default": null,
       "schema": {
         "type": [
@@ -63,7 +77,13 @@
           "integer",
           "array",
           "null"
-        ]
+        ],
+        "items": {
+          "type": [
+            "string",
+            "integer"
+          ]
+        }
       }
     },
     {
diff --git a/wrangles-docs/static/registry/contracts/standardize/custom.json b/wrangles-docs/static/registry/contracts/standardize/custom.json
index 0ac6884..f835faf 100644
--- a/wrangles-docs/static/registry/contracts/standardize/custom.json
+++ b/wrangles-docs/static/registry/contracts/standardize/custom.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/contracts/translate.json b/wrangles-docs/static/registry/contracts/translate.json
index 0a45340..c8a10ad 100644
--- a/wrangles-docs/static/registry/contracts/translate.json
+++ b/wrangles-docs/static/registry/contracts/translate.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "73c3ceb6-ffd8-4d74-8389-c83b99d33bb0",
diff --git a/wrangles-docs/static/registry/contracts/transpose.json b/wrangles-docs/static/registry/contracts/transpose.json
index 5468bbe..a55c057 100644
--- a/wrangles-docs/static/registry/contracts/transpose.json
+++ b/wrangles-docs/static/registry/contracts/transpose.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": "8716347f-f286-49b2-8a0b-cb73292e7475",
diff --git a/wrangles-docs/static/registry/contracts/try.json b/wrangles-docs/static/registry/contracts/try.json
index f2256f5..c0c445f 100644
--- a/wrangles-docs/static/registry/contracts/try.json
+++ b/wrangles-docs/static/registry/contracts/try.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.wrangles.com/registry/schema/wrangle-contract.schema.json",
   "format": "wrangles-registry-entry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "schema_version": "0.2",
   "type": "wrangle",
   "id": null,
diff --git a/wrangles-docs/static/registry/index.md b/wrangles-docs/static/registry/index.md
index 3a0f6cc..4ae7b11 100644
--- a/wrangles-docs/static/registry/index.md
+++ b/wrangles-docs/static/registry/index.md
@@ -4,7 +4,7 @@ type: collection
 title: Wrangles Registry
 description: Public pre-production bundle for Wrangles recipe primitives.
 status: pre-production
-registry_version: 0.2.0
+registry_version: 0.2.1
 ---
 
 # Wrangles Registry
diff --git a/wrangles-docs/static/registry/manifest.json b/wrangles-docs/static/registry/manifest.json
index 0265dfd..31f2379 100644
--- a/wrangles-docs/static/registry/manifest.json
+++ b/wrangles-docs/static/registry/manifest.json
@@ -1,6 +1,6 @@
 {
   "format": "wrangles-registry",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "contract_version": "0.2",
   "status": "pre-production",
   "compatibility": {
@@ -2491,117 +2491,117 @@
   "artifact_checksums": {
     "algorithm": "sha256",
     "files": {
-      "/registry/contracts/accordion.json": "d821b9170b19db9c89f74cb36f89a1d12a8a2b674f4ddd09593580ee83618752",
-      "/registry/contracts/batch.json": "18ade4f1c8190877006c0ab330e05f79570aa83e74ce9071c1ed8b85a5389ad3",
-      "/registry/contracts/classify.json": "7602bfaf8d1e87d492ae52ff8efe405c17e586ada22c379321e6309595b125f8",
-      "/registry/contracts/clean-whitespaces.json": "aae711f6b405397d404cb3234ce002fa6c99aea2e939ecd42ced80b256939cb0",
-      "/registry/contracts/compare/lists.json": "f6ff4d24d991b850284821af857ccd734cf67e4ffea81ad79282096e4249a569",
-      "/registry/contracts/compare/text.json": "c92bfb1b8e714b802c3a0f8f310f3a737cd2860213503ca0f6a9507045584eb2",
-      "/registry/contracts/compute/case-when.json": "00b6276f058d75a70c96a834c35af54231c51c9bad14b4aa0180a6b1f2b2733e",
-      "/registry/contracts/compute/score-search-results.json": "008e859873dc73af787bb8a448754d2d02469fd1799a212df78cd65f9f13a7f6",
-      "/registry/contracts/concurrent.json": "574cab03f212362402e121fea032172499c898fe9e3b1a4490eaf03f74520f44",
-      "/registry/contracts/convert/case.json": "d5b09a0f09411f8edc494943efaaf476462fdf3b44fe88863e3b64fe0b41124a",
-      "/registry/contracts/convert/data-type.json": "63af94c162402f1eea2f870183464bb6d3df0b1f93785b308bf32eb4eb4d93ca",
-      "/registry/contracts/convert/fraction-to-decimal.json": "8cc09a5a816b272eb27640ce4d6d41b130ac7c21383eac9905810c52c769b695",
-      "/registry/contracts/convert/from-json.json": "988b004cf69e657245a6100f60108b66a047c162e1b10d71ee9e038816888c58",
-      "/registry/contracts/convert/from-yaml.json": "ca8f7ce9c261a8b9372fc208ceb278e111cfae6cfc5d13c832d6b0a91c412bcc",
-      "/registry/contracts/convert/to-json.json": "03507552968dde1f59d4cc7032d41f87dda79cf7ee11c8f3e0ef31742cd42295",
-      "/registry/contracts/convert/to-yaml.json": "11f0279c17f1c308215c35fb74d4421d3cbcd130b94ceb65b8aba2b4441b5bb3",
-      "/registry/contracts/copy.json": "9b416697dd96f30af849ff7aa7e8c7b3bb6b18b1a8b2d9ab22fb12993b73a4d8",
-      "/registry/contracts/create/bins.json": "124939d9b76c51b31b3614b7d0695cd26055fa053fe78b986b5e8cca15faea03",
-      "/registry/contracts/create/column.json": "73a624c913e8517dc25134bc3ee441ba9bee76a5d70bb1ee49e19f096fdadae9",
-      "/registry/contracts/create/embeddings.json": "5c339710f6af29662b6117542948ff93ad1f6470a89b06bd6382c9df4b637f9e",
-      "/registry/contracts/create/guid.json": "98d324c79335b884f0f299d163d2655dd064fb6a499a6c679962373fd4503782",
-      "/registry/contracts/create/hash.json": "1b2b22d2c54084696119441c12d307e3eb380c1e4703f21c9935fce87b2523be",
-      "/registry/contracts/create/index.json": "53ac836f0186ac3190bb59b90f4d29632ace343ace9198fde938891f04d5f174",
-      "/registry/contracts/create/jinja.json": "3352d1ae5b8e3a5a373eeaab0f17e3659873a2572eaf7962fd36d34d14cd437d",
-      "/registry/contracts/create/uuid.json": "4f6924916863b97cc04bcb77bfd7256949aa5e66f1e50e1abad9e32e7a6f3972",
-      "/registry/contracts/date-calculator.json": "5ef783cc4b11c5ee870389583298a10c6ce492f0b40ac359cc44b4d95c34f78d",
-      "/registry/contracts/drop.json": "9297e90b1370058797a23869ed19a35679adfcd6093bc00e3d72ecc1fa31d777",
-      "/registry/contracts/explode.json": "260ed2f38f2c4127d3b6729c183616ecac68964d693d27e0fd6a75b687f7b96a",
-      "/registry/contracts/extract/address.json": "f0c0da7ab04fcaed34be00280a94353ec00f3aa1310875b4c7dc45bfdebd4586",
-      "/registry/contracts/extract/ai.json": "03fd23c3acf0bbb19c655623844b4f7a7e717ac5b71a50594e20e2a6609d295f",
-      "/registry/contracts/extract/attributes.json": "ca0adfeb8f24536b3c1100f9c842bef26b9c4161ecab7c8de3ac89320579c58a",
-      "/registry/contracts/extract/brackets.json": "fbff20c250f3115a51db11ecd8e6702b26f333dcc669cc09344b8f78bd0ebe05",
-      "/registry/contracts/extract/codes.json": "d272b955042af101ae86fc2225108c37fdb284725bdc6d82d50fceb116f5bbda",
-      "/registry/contracts/extract/custom.json": "90172e9fc3217d7055942901dfa9651e17db119ecb88a043bb558ddb4f61d7cd",
-      "/registry/contracts/extract/date-properties.json": "e4c9a6a3526465523db1976a08ada426a834e6b5a7b6bca2f03ea5341429c717",
-      "/registry/contracts/extract/date-range.json": "041cf361fdf3610da2f8014ca25195df7e64d0a8bbb7f6fa2838e70a86993e47",
-      "/registry/contracts/extract/html.json": "3f6e0d3860f0a110a7c92f640b5fde95b7f46160af93a2b74f63a334ce387eeb",
-      "/registry/contracts/extract/properties.json": "41c754c64caf205372b7e67716cfbb4fab98db6101fdfbb7108654b7e82e4826",
-      "/registry/contracts/extract/regex.json": "c0a83c436201606c3d7da3a62ddc3ca170281cc86a62bab5b13683fe8ec92145",
-      "/registry/contracts/filter.json": "4da05aeeecbf5def51fc9bdb9fe693c78bc3e77082bad2252adcaf2bf2d97d7d",
-      "/registry/contracts/format/dates.json": "74848e19862c9fb3510ed0531f87d40c7a679e932c052c133a3f60bf890eb2a1",
-      "/registry/contracts/format/pad.json": "a8e38647628604f9b8d2a46504dc97c9c9498119d417238e4b7c5a579df75d0d",
-      "/registry/contracts/format/prefix.json": "3eb88cf0fbbd6ae599dd924e837233299667e96fe81f1c239ef352fe314a79b3",
-      "/registry/contracts/format/price-breaks.json": "33c1816580f880b5a72b5a338303827e0c1cccb0b3a54ecb5f2703d3c5d29e64",
-      "/registry/contracts/format/remove-duplicates.json": "ae604dc56c94cfafd732952286db201a6af7bbdd7f8b9c0d2cee85fe844b4473",
-      "/registry/contracts/format/significant-figures.json": "c5297b3f91fb392e6ae248fe55b069ee2a6f7ad51322e5730bfd9edec64c3a82",
-      "/registry/contracts/format/suffix.json": "0602d57b974a73fe2ff39e257a1a7460bd340b8311722cc7ff69c2a5cd92eaf6",
-      "/registry/contracts/format/trim.json": "e4703843093f1961db1546df09554cedce6fbc46b9e51910ed27956001ae5825",
-      "/registry/contracts/generate/ai.json": "e5be3a5757bee5e718dd0582f615671096e9356843a6bc269a6f5a23490a70c9",
-      "/registry/contracts/huggingface.json": "ea857526e3f056384159dcc3f7ea71f6a11e07908f652d6b52dd207f67fa3941",
-      "/registry/contracts/log.json": "01d2cd22e37d0421e890bfb170e88eb93cedc5cbd35154ecccc51e4fb086b466",
-      "/registry/contracts/lookup.json": "a95d025a681777cf090cc6c366ffa1d166461e12b961f10a7b6c8461ccbb2fd9",
-      "/registry/contracts/math.json": "6b800ecc277a2fcca8ffba485c6462468bbcaf9afe05214ac8545196e0036024",
-      "/registry/contracts/maths.json": "f56cb6e0841c5b1853ea51fe35eb6db47ac71d3c92fe30c12688bf1b9be490b6",
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       "/registry/runtime/wranglespy.json": "f06526b3823fb70f1bb28f4be242bf23621d1b5a544d1f42c04b7549fe1bbef0",
-      "/registry/schema/wrangle-contract.schema.json": "78712d241d35dad90525da0a0a9e84e939a9acb6f5eaaff5e26d7617819cafff",
-      "/registry/schema/wrangle-entry.schema.json": "edfcb522624d469a5e6565fec07ba151f24d3a3ebfe1888826b189977cadfb3e",
+      "/registry/schema/wrangle-contract.schema.json": "48c3ed261fc5046df85cedc76ef549b720e94a75b828706c2faaf87f54b8eea3",
+      "/registry/schema/wrangle-entry.schema.json": "42f0aeae27e96144b7aa83d9623e262171b3f2cb91e4cd8ee6e75da66b28460b",
       "/registry/schema/wrangles-runtime-manifest.schema.json": "fc05d2e44272311d3875421c5ae9b978185fcc05770d330cc4cd5bd261ec7538",
-      "/schemas/recipes/registry/recipe-writer.schema.json": "d8fd259ba2fac003a6a965b7113c13b301deb3c00a90825a6e8e648c0b386f92",
-      "/schemas/recipes/registry/schema.json": "135d01a7ae465cda309e9c07c3259a1c65a1e04ae057d7e54d6f60e3732c5322"
+      "/schemas/recipes/registry/recipe-writer.schema.json": "02de487d6e8eade0424b23a484bd0b1301871faf1974defae4b9970720e0eb74",
+      "/schemas/recipes/registry/schema.json": "72e4a09c3e713227c4410099fbf26dfbe351467455187cfa506e7e5bfb786ff3"
     }
   },
   "bundle_checksum": {
     "algorithm": "sha256",
     "framing": "utf8-path-null-content-null-v1",
-    "value": "ccf8cf048d7440b6a30b24d6a31bcde6718b763519a819086146144f0fde81b7",
+    "value": "bd1e20a259cc254173d9dfd45abdfdf588b851ba0bd969c12d3d3802e3b22513",
     "member_count": 105,
     "manifest_included": false
   }
diff --git a/wrangles-docs/static/registry/runtime/reconciliation.json b/wrangles-docs/static/registry/runtime/reconciliation.json
index 9572611..b65467f 100644
--- a/wrangles-docs/static/registry/runtime/reconciliation.json
+++ b/wrangles-docs/static/registry/runtime/reconciliation.json
@@ -1,6 +1,6 @@
 {
   "format": "wrangles-runtime-reconciliation-summary",
-  "registry_version": "0.2.0",
+  "registry_version": "0.2.1",
   "runtime_source": {
     "repository": "https://github.com/wrangleworks/WranglesPY",
     "version": "1.20.2",
diff --git a/wrangles-docs/static/registry/schema/wrangle-contract.schema.json b/wrangles-docs/static/registry/schema/wrangle-contract.schema.json
index 083459a..b5cc11a 100644
--- a/wrangles-docs/static/registry/schema/wrangle-contract.schema.json
+++ b/wrangles-docs/static/registry/schema/wrangle-contract.schema.json
@@ -39,7 +39,7 @@
       "const": "wrangles-registry-entry"
     },
     "registry_version": {
-      "const": "0.2.0"
+      "const": "0.2.1"
     },
     "schema_version": {
       "const": "0.2"
@@ -281,6 +281,9 @@
             "Details"
           ]
         },
+        "column_semantics": {
+          "$ref": "#/$defs/column_semantics"
+        },
         "runtime_default": {},
         "schema": {
           "type": "object",
@@ -288,6 +291,31 @@
         }
       }
     },
+    "column_semantics": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": [
+        "role",
+        "cardinality"
+      ],
+      "properties": {
+        "role": {
+          "enum": [
+            "reference",
+            "destination"
+          ],
+          "description": "Whether the parameter selects columns that exist before the step or names columns where the step writes results."
+        },
+        "cardinality": {
+          "enum": [
+            "scalar",
+            "list",
+            "scalar_or_list"
+          ],
+          "description": "Whether the parameter accepts one direct string/integer column identifier, an array whose direct items are string/integer identifiers, or either shape. Nullability is defined separately by the parameter schema; object and mapping-key locations require a future locator vocabulary."
+        }
+      }
+    },
     "example": {
       "type": "object",
       "additionalProperties": false,
diff --git a/wrangles-docs/static/registry/schema/wrangle-entry.schema.json b/wrangles-docs/static/registry/schema/wrangle-entry.schema.json
index 01821af..f81fa57 100644
--- a/wrangles-docs/static/registry/schema/wrangle-entry.schema.json
+++ b/wrangles-docs/static/registry/schema/wrangle-entry.schema.json
@@ -283,6 +283,9 @@
             "Details"
           ]
         },
+        "column_semantics": {
+          "$ref": "#/$defs/column_semantics"
+        },
         "runtime_default": {},
         "schema": {
           "type": "object",
@@ -290,6 +293,31 @@
         }
       }
     },
+    "column_semantics": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": [
+        "role",
+        "cardinality"
+      ],
+      "properties": {
+        "role": {
+          "enum": [
+            "reference",
+            "destination"
+          ],
+          "description": "Whether the parameter selects columns that exist before the step or names columns where the step writes results."
+        },
+        "cardinality": {
+          "enum": [
+            "scalar",
+            "list",
+            "scalar_or_list"
+          ],
+          "description": "Whether the parameter accepts one direct string/integer column identifier, an array whose direct items are string/integer identifiers, or either shape. Nullability is defined separately by the parameter schema; object and mapping-key locations require a future locator vocabulary."
+        }
+      }
+    },
     "example": {
       "type": "object",
       "additionalProperties": false,
diff --git a/wrangles-docs/static/registry/wrangles/_root/drop.md b/wrangles-docs/static/registry/wrangles/_root/drop.md
index 7435a7e..9c5c190 100644
--- a/wrangles-docs/static/registry/wrangles/_root/drop.md
+++ b/wrangles-docs/static/registry/wrangles/_root/drop.md
@@ -34,10 +34,15 @@ parameters:
     description: Name of the column(s) to drop.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar_or_list
     schema:
       type:
         - string
         - array
+      items:
+        type: string
 examples: []
 sources:
   - id: runtime
diff --git a/wrangles-docs/static/registry/wrangles/_root/rename.md b/wrangles-docs/static/registry/wrangles/_root/rename.md
index 2dee332..e90e42e 100644
--- a/wrangles-docs/static/registry/wrangles/_root/rename.md
+++ b/wrangles-docs/static/registry/wrangles/_root/rename.md
@@ -35,6 +35,9 @@ parameters:
     description: Name or list of input columns.
     required: false
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar_or_list
     runtime_default: null
     schema:
       type:
@@ -42,16 +45,25 @@ parameters:
         - integer
         - array
         - 'null'
+      items:
+        type:
+          - string
+          - integer
   - name: output
     description: Name or list of output columns.
     required: false
     param_group: I/O
+    column_semantics:
+      role: destination
+      cardinality: scalar_or_list
     runtime_default: null
     schema:
       type:
         - string
         - array
         - 'null'
+      items:
+        type: string
   - name: wrangles
     description: >-
       Use wrangles to transform the column names. The input is named 'columns' and the final result
diff --git a/wrangles-docs/static/registry/wrangles/extract/date-range.md b/wrangles-docs/static/registry/wrangles/extract/date-range.md
index 7a4d4f3..ee36c9d 100644
--- a/wrangles-docs/static/registry/wrangles/extract/date-range.md
+++ b/wrangles-docs/static/registry/wrangles/extract/date-range.md
@@ -34,18 +34,27 @@ parameters:
     description: Name of the start date column.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar
     schema:
       type: string
   - name: end_time
     description: Name of the end date column.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar
     schema:
       type: string
   - name: output
     description: Name of the output column.
     required: true
     param_group: I/O
+    column_semantics:
+      role: destination
+      cardinality: scalar
     schema:
       type: string
   - name: range
diff --git a/wrangles-docs/static/registry/wrangles/standardize/clean.md b/wrangles-docs/static/registry/wrangles/standardize/clean.md
index fced91a..1eb6053 100644
--- a/wrangles-docs/static/registry/wrangles/standardize/clean.md
+++ b/wrangles-docs/static/registry/wrangles/standardize/clean.md
@@ -36,15 +36,25 @@ parameters:
     description: Name or list of input columns.
     required: true
     param_group: I/O
+    column_semantics:
+      role: reference
+      cardinality: scalar_or_list
     schema:
       type:
         - string
         - integer
         - array
+      items:
+        type:
+          - string
+          - integer
   - name: output
     description: Name or list of output columns. Defaults to overwriting input.
     required: false
     param_group: I/O
+    column_semantics:
+      role: destination
+      cardinality: scalar_or_list
     runtime_default: null
     schema:
       type:
@@ -52,6 +62,10 @@ parameters:
         - integer
         - array
         - 'null'
+      items:
+        type:
+          - string
+          - integer
   - name: fix_encoding
     description: Repair mojibake and other reversible encoding errors.
     required: false
diff --git a/wrangles-docs/static/schemas/recipes/registry/recipe-writer.schema.json b/wrangles-docs/static/schemas/recipes/registry/recipe-writer.schema.json
index 57459a4..8865ad8 100644
--- a/wrangles-docs/static/schemas/recipes/registry/recipe-writer.schema.json
+++ b/wrangles-docs/static/schemas/recipes/registry/recipe-writer.schema.json
@@ -1516,7 +1516,14 @@
                   "string",
                   "array"
                 ],
-                "description": "Name of the column(s) to drop."
+                "items": {
+                  "type": "string"
+                },
+                "description": "Name of the column(s) to drop.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar_or_list"
+                }
               },
               "if": {
                 "type": "string",
@@ -2440,15 +2447,27 @@
             "properties": {
               "start_time": {
                 "type": "string",
-                "description": "Name of the start date column."
+                "description": "Name of the start date column.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar"
+                }
               },
               "end_time": {
                 "type": "string",
-                "description": "Name of the end date column."
+                "description": "Name of the end date column.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar"
+                }
               },
               "output": {
                 "type": "string",
-                "description": "Name of the output column."
+                "description": "Name of the output column.",
+                "x-wrangles-column": {
+                  "role": "destination",
+                  "cardinality": "scalar"
+                }
               },
               "range": {
                 "type": "string",
@@ -5315,7 +5334,17 @@
                   "integer",
                   "array"
                 ],
-                "description": "Name or list of input columns."
+                "items": {
+                  "type": [
+                    "string",
+                    "integer"
+                  ]
+                },
+                "description": "Name or list of input columns.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar_or_list"
+                }
               },
               "output": {
                 "type": [
@@ -5324,7 +5353,17 @@
                   "array",
                   "null"
                 ],
+                "items": {
+                  "type": [
+                    "string",
+                    "integer"
+                  ]
+                },
                 "description": "Name or list of output columns. Defaults to overwriting input.",
+                "x-wrangles-column": {
+                  "role": "destination",
+                  "cardinality": "scalar_or_list"
+                },
                 "default": null
               },
               "fix_encoding": {
diff --git a/wrangles-docs/static/schemas/recipes/registry/schema.json b/wrangles-docs/static/schemas/recipes/registry/schema.json
index 741e2c6..65fcbeb 100644
--- a/wrangles-docs/static/schemas/recipes/registry/schema.json
+++ b/wrangles-docs/static/schemas/recipes/registry/schema.json
@@ -1628,7 +1628,14 @@
                   "string",
                   "array"
                 ],
-                "description": "Name of the column(s) to drop."
+                "items": {
+                  "type": "string"
+                },
+                "description": "Name of the column(s) to drop.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar_or_list"
+                }
               },
               "if": {
                 "type": "string",
@@ -2552,15 +2559,27 @@
             "properties": {
               "start_time": {
                 "type": "string",
-                "description": "Name of the start date column."
+                "description": "Name of the start date column.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar"
+                }
               },
               "end_time": {
                 "type": "string",
-                "description": "Name of the end date column."
+                "description": "Name of the end date column.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar"
+                }
               },
               "output": {
                 "type": "string",
-                "description": "Name of the output column."
+                "description": "Name of the output column.",
+                "x-wrangles-column": {
+                  "role": "destination",
+                  "cardinality": "scalar"
+                }
               },
               "range": {
                 "type": "string",
@@ -4311,7 +4330,17 @@
                   "array",
                   "null"
                 ],
+                "items": {
+                  "type": [
+                    "string",
+                    "integer"
+                  ]
+                },
                 "description": "Name or list of input columns.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar_or_list"
+                },
                 "default": null
               },
               "output": {
@@ -4320,7 +4349,14 @@
                   "array",
                   "null"
                 ],
+                "items": {
+                  "type": "string"
+                },
                 "description": "Name or list of output columns.",
+                "x-wrangles-column": {
+                  "role": "destination",
+                  "cardinality": "scalar_or_list"
+                },
                 "default": null
               },
               "wrangles": {
@@ -5771,7 +5807,17 @@
                   "integer",
                   "array"
                 ],
-                "description": "Name or list of input columns."
+                "items": {
+                  "type": [
+                    "string",
+                    "integer"
+                  ]
+                },
+                "description": "Name or list of input columns.",
+                "x-wrangles-column": {
+                  "role": "reference",
+                  "cardinality": "scalar_or_list"
+                }
               },
               "output": {
                 "type": [
@@ -5780,7 +5826,17 @@
                   "array",
                   "null"
                 ],
+                "items": {
+                  "type": [
+                    "string",
+                    "integer"
+                  ]
+                },
                 "description": "Name or list of output columns. Defaults to overwriting input.",
+                "x-wrangles-column": {
+                  "role": "destination",
+                  "cardinality": "scalar_or_list"
+                },
                 "default": null
               },
               "fix_encoding": {