diff --git a/.github/hooks/validate-a2ml.sh b/.github/hooks/validate-a2ml.sh
index b053676..41bff11 100755
--- a/.github/hooks/validate-a2ml.sh
+++ b/.github/hooks/validate-a2ml.sh
@@ -2,9 +2,9 @@
 # SPDX-License-Identifier: MPL-2.0
 # Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath) <j.d.a.jewell@open.ac.uk>
 #
-# validate-a2ml.sh — A2ML manifest validation script
+# validate-a2ml.sh — A2ML and DEED manifest validation script
 #
-# Scans for .a2ml files and validates:
+# Scans for .a2ml and .deed files and validates:
 #   1. Required fields: agent-id or pedigree name, version
 #   2. SPDX-License-Identifier header presence
 #   3. Attestation block structure (if present)
@@ -89,7 +89,7 @@ report_issue() {
 }
 
 # ---------------------------------------------------------------------------
-# Validator: check a single .a2ml file
+# Validator: check a single manifest file
 # ---------------------------------------------------------------------------
 validate_a2ml() {
     local file="$1"
@@ -281,15 +281,15 @@ validate_a2ml() {
 }
 
 # ---------------------------------------------------------------------------
-# Main: discover and validate .a2ml files
+# Main: discover and validate .a2ml and .deed files
 # ---------------------------------------------------------------------------
 
-echo "::group::A2ML Manifest Validation"
-echo "Scanning ${SCAN_PATH} for .a2ml files..."
+echo "::group::A2ML and DEED Manifest Validation"
+echo "Scanning ${SCAN_PATH} for .a2ml and .deed files..."
 echo ""
 
-# Find all .a2ml files, excluding .git directory
-mapfile -t a2ml_candidates < <(find "$SCAN_PATH" -name '*.a2ml' -not -path '*/.git/*' -type f | sort)
+# Find all supported manifest files, excluding the .git directory.
+mapfile -t a2ml_candidates < <(find "$SCAN_PATH" -type f \( -name '*.a2ml' -o -name '*.deed' \) -not -path '*/.git/*' | sort)
 
 # Apply paths-ignore filter
 a2ml_files=()
@@ -307,7 +307,7 @@ if [[ $SKIPPED -gt 0 ]]; then
 fi
 
 if [[ ${#a2ml_files[@]} -eq 0 ]]; then
-    echo "::notice::No .a2ml files found in ${SCAN_PATH}"
+    echo "::notice::No .a2ml or .deed files found in ${SCAN_PATH}"
     echo "files_scanned=0" >> "$GITHUB_OUTPUT_FILE" 2>/dev/null || true
     echo "errors=0" >> "$GITHUB_OUTPUT_FILE" 2>/dev/null || true
     echo "warnings=0" >> "$GITHUB_OUTPUT_FILE" 2>/dev/null || true
@@ -315,7 +315,7 @@ if [[ ${#a2ml_files[@]} -eq 0 ]]; then
     exit 0
 fi
 
-echo "Found ${#a2ml_files[@]} .a2ml file(s)"
+echo "Found ${#a2ml_files[@]} manifest file(s) (.a2ml or .deed)"
 echo ""
 
 for file in "${a2ml_files[@]}"; do
diff --git a/.github/workflows/dogfood-gate.yml b/.github/workflows/dogfood-gate.yml
index 9503261..69a27eb 100644
--- a/.github/workflows/dogfood-gate.yml
+++ b/.github/workflows/dogfood-gate.yml
@@ -21,7 +21,7 @@ jobs:
   # Job 1: A2ML manifest validation
   # ---------------------------------------------------------------------------
   a2ml-validate:
-    name: Validate A2ML manifests
+    name: Validate DEED manifests
     runs-on: ubuntu-latest
 
     steps:
@@ -31,10 +31,10 @@ jobs:
       - name: Check for A2ML files
         id: detect
         run: |
-          COUNT=$(find . -name '*.a2ml' -not -path './.git/*' | wc -l)
+          COUNT=$(find . \( -name '*.a2ml' -o -name '*.deed' \) -not -path './.git/*' | wc -l)
           echo "count=$COUNT" >> "$GITHUB_OUTPUT"
           if [ "$COUNT" -eq 0 ]; then
-            echo "::warning::No .a2ml manifest files found. Every RSR repo should have 0-AI-MANIFEST.a2ml"
+            echo "::warning::No .a2ml/.deed manifest files found. Every RSR repo should have a repo deed (<reponame>_chora.deed); legacy 0-AI-MANIFEST.a2ml accepted mid-migration — standards #837"
           fi
 
       - name: Validate A2ML manifests
@@ -47,14 +47,14 @@ jobs:
             cat <<'EOF' >> "$GITHUB_STEP_SUMMARY"
           ## A2ML Validation
 
-          :warning: **No .a2ml files found.** Every RSR-compliant repo should have at least `0-AI-MANIFEST.a2ml`.
+          :warning: **No .a2ml/.deed manifest files found.** Every RSR-compliant repo should have a repo deed (`<reponame>_chora.deed`) at its root.
 
-          Create one with: `a2mliser init` or copy from [rsr-template-repo](https://github.com/hyperpolymath/rsr-template-repo).
+          Copy it from [rsr-template-repo](https://github.com/hyperpolymath/rsr-template-repo).
           EOF
           else
             echo "## A2ML Validation" >> "$GITHUB_STEP_SUMMARY"
             echo "" >> "$GITHUB_STEP_SUMMARY"
-            echo "Scanned **${A2ML_COUNT}** .a2ml file(s). See step output for details." >> "$GITHUB_STEP_SUMMARY"
+            echo "Scanned **${A2ML_COUNT}** manifest file(s) (.deed, or legacy .a2ml). See step output for details." >> "$GITHUB_STEP_SUMMARY"
           fi
 
   # ---------------------------------------------------------------------------
@@ -92,7 +92,7 @@ jobs:
             cat <<'EOF' >> "$GITHUB_STEP_SUMMARY"
           ## K9 Contract Validation
 
-          :warning: **No K9 contract files found.** Repos with configuration files should have K9 contracts.
+          :warning: **No K9 contracts found.** Generate contracts with `k9iser generate .`.
 
           Generate contracts with: `k9iser generate .`
           EOF
@@ -306,7 +306,7 @@ jobs:
           MAX=6
 
           # A2ML manifest present?
-          if find . -name '*.a2ml' -not -path './.git/*' | head -1 | grep -q .; then
+          if find . \( -name '*.a2ml' -o -name '*.deed' \) -not -path './.git/*' | head -1 | grep -q .; then
             SCORE=$((SCORE + 1))
             A2ML_STATUS=":white_check_mark:"
           else
@@ -360,7 +360,7 @@ jobs:
 
           | Tool/Format | Status | Notes |
           |-------------|--------|-------|
-          | A2ML manifest (0-AI-MANIFEST.a2ml) | ${A2ML_STATUS} | Required for all RSR repos |
+          | DEED repo deed (`<reponame>_chora.deed`) | ${A2ML_STATUS} | Required for all RSR repos |
           | K9 contracts | ${K9_STATUS} | Required for repos with config files |
           | .editorconfig | ${EC_STATUS} | Required for all repos |
           | Groove endpoint | ${GROOVE_STATUS} | Required for service repos |