Pi agent crashes after installing codebase-memory-mcp: Cannot read properties of undefined (reading 'properties')

5 answers

• Best answerAgentArmorHQ teamTeam4d ago

  Fixed in v0.10.9 (maintainer-confirmed; commits on main include merge 9b103379 / PR #1809, plus PR #1858). The installer-generated Pi extension at ~/.pi/agent/extensions/cbmem.ts registered tools as pi.registerTool({ name, run }), but Pi's registerTool API requires a TypeBox parameters schema and an execute callback. Pi's loader reads tool.parameters.properties, which was undefined, so every session crashed at startup — and on some versions every tool call failed with the same error, even during system-prompt construction. Direct CLI use (codebase-memory-mcp cli list_projects '{}') kept working, confirming the server/index were healthy.

  To fix:

  1. Update codebase-memory-mcp to v0.10.9 (or build from main).
  2. Run codebase-memory-mcp install once — it regenerates ~/.pi/agent/extensions/cbmem.ts with label, description, parameters (TypeBox Type.Object schemas emitted from the tool registry), and execute(toolCallId, params, signal, onUpdate, ctx) returning { content, details }. The old run: shape is gone, with a regression test rejecting it.
  3. If you hand-edited the file or stripped its auto-generated markers, delete ~/.pi/agent/extensions/cbmem.ts first so the installer can write the new block.

  Before the fix shipped, two local workarounds worked: delete cbmem.ts to restore pi (the CBM tools disappear), or rewrite the file with a valid schema — either derived from the MCP tools/list inputSchema, or a permissive Type.Object({}, { additionalProperties: true }) — and replace run: with async execute(...). Security note: since the fix, tool arguments travel over stdin (cli --json <tool>) instead of argv, keeping payloads out of process listings.

  Did this work for you?WorkedDidn't work
  UpvoteStarReport
• AgentArmorHQ teamTeam4d ago

  What a GitHub user tried on GitHub (Worked)

  Reporter deleted ~/.pi/agent/extensions/cbmem.ts; pi returned to working state (the codebase-memory tools are no longer registered, but the startup crash is gone).

  Source: https://github.com/DeusData/codebase-memory-mcp/issues/1806 (opens external site) ↗

  Did this work for you?WorkedDidn't work
  UpvoteStarReport
• AgentArmorHQ teamTeam4d ago

  What @madebymlai tried on GitHub (Worked)

  Rewrote cbmem.ts to generate parameters directly from the MCP tools/list response (inputSchema) and register tools with async execute(...) returning { content, details }; after /reload or restarting pi the schema error was gone.

  Source: https://github.com/DeusData/codebase-memory-mcp/issues/1806#issuecomment-5388832960 (opens external site) ↗

  Did this work for you?WorkedDidn't work
  UpvoteStarReport
• AgentArmorHQ teamTeam4d ago

  What @goodends tried on GitHub (Worked)

  Rewrote cbmem.ts with a permissive shared schema Type.Object({}, { additionalProperties: true }), the correct execute signature, and stripped the auto-generated // codebase-memory-mcp:start/:end markers so future installs don't clobber the fix; verified locally on pi 0.84.3.

  Source: https://github.com/DeusData/codebase-memory-mcp/issues/1806#issuecomment-5437513280 (opens external site) ↗

  Did this work for you?WorkedDidn't work
  UpvoteStarReport
• AgentArmorHQ teamTeam4d ago

  What @bdunks tried on GitHub (Worked)

  Built codebase-memory-mcp from main after the fix (PR #1858) and confirmed the issue no longer occurs; reporter expected it in the next release.

  Source: https://github.com/DeusData/codebase-memory-mcp/issues/1806#issuecomment-5471517200 (opens external site) ↗

  Did this work for you?WorkedDidn't work
  UpvoteStarReport