engram-plugin-thin

## When to Use Use this skill when: - Editing plugin hooks/scripts/adapters - Adding passive/active memory capture integrations - Wiring agent-specific setup behavior --- ## Boundary Rules 1. Keep adapters thin: parse input, call API/tool, return. 2. Put complex logic in Go core (`store/server/mcp`). 3. Avoid extra runtime dependencies in plugin scripts. 4. Reuse a shared contract across all supported agents. --- ## Narrow Pi Exception: Observation-Save Acknowledgement Recovery `plugin/pi` native `mem_save` may resolve only an ambiguous acknowledgement because the Go server cannot observe that a client lost one. Go remains the sole authority for the durable ledger, canonical fingerprint, validation, conflicts, tombstones, retention, and mutation effects. - Generate one operation UUID before the initial dispatch and freeze the exact redacted payload and both destinations. - On ambiguity, query only authoritative `GET /observations/save-result`. A typed `404` with code `observation_save_result_not_found` permits one exact replay after the cancellable 250 ms backoff. A positive replay receipt succeeds immediately; only an ambiguous replay, including a replay `409` or `410`, gets one final GET. - Keep existing total-deadline and caller-cancellation bounds. A lookup confirms success only with a positive ID and `status: "committed"`; a successful initial POST retains legacy positive `{id}` acknowledgement compatibility. - Initial received HTTP errors remain typed and never replay or self-heal. Caller cancellation is propagated; unresolved write uncertainty remains unknown, never saved. - This exception grants no other route or tool retry authority, no general retry framework, no local business ledger decision, and no telemetry exemption. Timing telemetry may not log the operation UUID; it grants no broader logging permission or change to existing user-facing unknown-outcome diagnostics that expose it for read-only lookup. --- ## Compatibility Checklist - [ ] Claude Code flow still works - [ ] OpenCode flow still works - [ ] Gemini/Codex config paths remain valid - [ ] Docs reflect real integration behavior