fix(mcp): actionable error when [mcp] extra is missing (#159)#162
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fix(mcp): actionable error when [mcp] extra is missing (#159)#162J0nd1sk wants to merge 1 commit into
J0nd1sk wants to merge 1 commit into
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`brainctl-mcp` (entry point agentmemory.mcp_server:run) imported the MCP SDK at module top level with no guard. On a plain `pip install brainctl` / `pipx install brainctl` (no `[mcp]` extra) it died with a bare `ModuleNotFoundError: No module named 'mcp'` traceback, and the MCP client only reported "failed to connect" — giving the user no idea an extra was required. Guard the import and exit(1) with the exact fix (`pip install 'brainctl[mcp]'`, plus the pipx-inject variant). Also clarify the README Install section so `[mcp]` is presented as part of the install command, not an optional second step. Fixes #159 Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Closes #159.
Problem
brainctl-mcpimported the MCP SDK unguarded atmcp_server.py:36. Without the optional[mcp]extra (the default forpip install brainctl/pipx install brainctl), it crashed with a bareModuleNotFoundError, surfacing to MCP clients only as "failed to connect."Fix
from mcp.server import Server; on a missingmcppackage, write an actionable hint to stderr (pip install 'brainctl[mcp]', plus thepipx injectvariant) andexit(1). Any otherModuleNotFoundErrorre-raises unchanged.[mcp]reads as part of the install command, not an optional second step.Test
tests/test_mcp_missing_extra.pyruns the server import in a subprocess withmcpblocked at import time and asserts a cleanexit(1)with the hint (no traceback). Normal import path (withmcppresent) is unaffected.Verification