@psraghuveer/memento-server

The MCP server adapter. Translates @modelcontextprotocol/sdk tool calls into invocations of the @psraghuveer/memento-core command registry.

This package owns the stdio transport and the MCP-tool surface. Anything beyond MCP-protocol concerns belongs in @psraghuveer/memento-core — the structural parity between the MCP adapter and the @psraghuveer/memento adapter is the entire point of ADR 0003.

buildMementoServer projects the @psraghuveer/memento-core command registry as MCP tools; serveStdio wires it to stdio. Used by memento serve.

Session-start instructions

The server emits a canonical session-start teaching spine on every initialize handshake (ADR-0026). It covers the session-start contract: when to call get_memory_context, when to write, when to confirm, the topic: value first-line rule, supersede-not-update, the silent-plumbing rule, and the secrets prohibition.

The MCP spec defines instructions as an optional field on the initialize response — client implementations choose whether to surface the value to the assistant's system prompt. Observed behaviour across current clients varies considerably; in many implementations the field is silently dropped. Treat the spine as best-effort future-proofing: present on every connect, harmless on clients that drop it, may pay off as client implementations evolve.

For reliable always-on teaching, the persona snippet (the universal fallback the user pastes into the client's custom-instructions slot) is the load-bearing surface. The bundled skill carries deeper distillation rules on intent for skill-capable clients. See docs/guides/teach-your-assistant.md for the three-surface walkthrough.

The text is exported as MEMENTO_INSTRUCTIONS from the package root. Hosts that embed buildMementoServer can override it via the info.instructions constructor option — the override replaces the spine entirely, so an operator wanting "spine + addendum" concatenates \${MEMENTO_INSTRUCTIONS}\n\n${addendum}`` explicitly.

MCP resource and prompt

In addition to tools, the server exposes:

• Resource memento://context — returns ranked context as JSON (equivalent to calling memory.context).
• Prompt session-context — accepts an optional focus argument. Without focus, it calls memory.context for query-less ranked retrieval. With focus, it calls memory.search using the value as the query.