feat: R2 — honest retrieval metadata on every recall

AGENTS.md

@@ -63,6 +63,11 @@ host is recallable from all of them. Not installed yet? Follow
   number of hits one query returns. Absence of results is absence of
   results, not evidence of absence — vary the wording or narrow by tag
   before concluding anything.
+- Every recall answer carries a `retrieval` block that says how it was
+  produced — read it instead of guessing: `truncated: true` means the
+  window filled and more may exist; `degraded: true` means semantic search
+  is configured but could not run, so you are seeing keyword-only results
+  right now (worth telling the user, and `memesh doctor` explains why).
 
 ## What Claude Code already does — do not double-write
 

CHANGELOG.md

@@ -6,6 +6,22 @@ All notable changes to MeMesh are documented here.
 
 ### Added
 
+- **Honest retrieval metadata: every recall says how it was answered.**
+  The envelope (MCP, HTTP and `--json` alike) now carries
+  `retrieval: { mode, degraded, truncated }` — `mode` is `hybrid` when the
+  vector supplement actually ran and `fts` when the answer is
+  keyword-only; `degraded: true` means embeddings ARE configured but the
+  vector side could not run right now (provider failure or missing
+  sqlite-vec), which until now silently served keyword-only results with
+  nothing in the response saying so; `truncated: true` means the results
+  filled `limit` and more may exist — the difference between "that is
+  all" and "that is all I was allowed to return". The CLI prints a
+  degraded warning and a "(limit reached — more may exist)" note in human
+  output. One shape change rides along: `memesh recall --json` now always
+  prints the object envelope (`{entities, retrieval, conflicts?}`) instead
+  of a bare array normally and an object only when conflicts existed —
+  the bimodal shape MCP and HTTP already abandoned.
+
 - **`memesh why <file>` + `POST /v1/why`: file attribution with typed
   abstentions.** Local git resolves which commits touched a file
   (`git log --follow`, or `git blame` for `--line N`); the graph answers

dist/core/operations.d.ts

@@ -2,10 +2,19 @@ import type { EmbedOutcome } from './embedder.js';
 import type { RememberInput, RememberResult, RecallInput, ForgetInput, ForgetResult, LearnInput, LearnResult, Entity } from './types.js';
 export declare function remember(args: RememberInput): RememberResult;
 export declare function recall(args: RecallInput): Entity[];
-export declare function recallEnhanced(args: RecallInput): Promise<Entity[]>;
+export interface RetrievalMeta {
+    mode: 'fts' | 'hybrid';
+    degraded: boolean;
+    truncated: boolean;
+}
+export declare function recallEnhanced(args: RecallInput): Promise<{
+    entities: Entity[];
+    retrieval: RetrievalMeta;
+}>;
 export declare function recallWithConflicts(args: RecallInput): Promise<{
     entities: Entity[];
     conflicts: string[];
+    retrieval: RetrievalMeta;
 }>;
 export { exportMemories, importMemories } from './serializer.js';
 export declare function learn(args: LearnInput): LearnResult;