fix(mcp): remember tool output validation — schema vs handler mismatches

The remember tool failed MCP output validation on every code path because
the declared schema did not match what the handler actually returns:

(1) memory_id / merged_with declared "type": "string" (UUID-style) but the
    handler returns int (PG bigint). Aligned with anchor.py / forget.py /
    get_causal_chain.py which already declare integer.

(2) Schema invariant required:["stored","action"] was violated by both
    no_content early-exit paths in remember.py and by
    write_gate.build_rejection_response(): they returned {"stored": false,
    ...} with no "action" field. Added "action": "rejected" to each.

(3) Schema enum was ["stored","merged","rejected"] (past-tense outcomes)
    but the handler forwarded the internal curation vocab "create"/"link"
    untouched, so every successful create/link failed with:
        Output validation error: 'create' is not one of [...]
    Normalized at the response boundary in build_response:
        create/link → "stored", merge → "merged".

After these fixes the schema invariant and the enum constraint are both
honoured on every code path (no_content, gate-rejected, created, linked,
merged).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: cdeust

mcp_server/core/write_gate.py

@@ -141,6 +141,7 @@ def build_rejection_response(
     """Build response when write gate rejects the memory."""
     return {
         "stored": False,
+        "action": "rejected",
         "reason": gate_reason,
         "novelty": _describe_signals(
             embedding_novelty,

mcp_server/handlers/remember.py

@@ -39,8 +39,8 @@
                 "description": "True if content landed in the memory store (as new row or a merge into an existing one).",
             },
             "memory_id": {
-                "type": "string",
-                "description": "UUID of the resulting memory row. Present when stored=true.",
+                "type": "integer",
+                "description": "ID of the resulting memory row (PG bigint). Present when stored=true.",
             },
             "action": {
                 "type": "string",
@@ -52,8 +52,8 @@
                 "description": "Human-readable explanation of the gate decision (e.g. 'low surprise', 'high entity overlap').",
             },
             "merged_with": {
-                "type": "string",
-                "description": "UUID of the existing memory when action=merged.",
+                "type": "integer",
+                "description": "ID of the existing memory (PG bigint) when action=merged.",
             },
             "heat": {
                 "type": "number",
@@ -260,15 +260,15 @@ def _parse_args(
 async def _handler_impl(args: dict[str, Any] | None = None) -> dict[str, Any]:
     """Store a memory with thermodynamic properties and predictive coding gate."""
     if not args or not args.get("content"):
-        return {"stored": False, "reason": "no_content"}
+        return {"stored": False, "action": "rejected", "reason": "no_content"}
 
     # Phase 7: harden user-controlled content at the ingestion boundary
     # (NFC normalization, control/bidi strip, byte cap).
     from mcp_server.shared.content_hardening import harden_content
 
     args["content"] = harden_content(args["content"])
     if not args["content"]:
-        return {"stored": False, "reason": "no_content"}
+        return {"stored": False, "action": "rejected", "reason": "no_content"}
 
     (
         content,

mcp_server/handlers/remember_response.py

@@ -66,10 +66,14 @@ def build_response(
     interf: float,
 ) -> dict[str, Any]:
     """Build the full success response dict."""
+    # Normalize internal curation action vocab → schema-canonical enum.
+    # try_curation returns "create"/"link" (present-tense ops); the public
+    # schema documents past-tense outcomes (stored / merged / rejected).
+    schema_action = {"create": "stored", "link": "stored", "merge": "merged"}.get(action, action)
     result = {
         "stored": True,
         "memory_id": mem_id,
-        "action": action,
+        "action": schema_action,
         "store_type": stype,
         "domain": domain,
         "heat": round(mod["heat"], 4),