mcp: run tool calls in worker threads - #312
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FastMCP awaits an async tool but calls a sync one inline on the event loop. Every tool here is sync and makes a blocking request, so calls were serialised across all sessions: measured against a running server, a trivial list_trees took 58.66s instead of 0.14s while one slow call was in flight. Register an async wrapper that hands the call to a worker thread. The dashboard tools funnel through one registration site and inherit this; the Maestro tools are wrapped individually, so a new one needs the decorator adding. Concurrency also makes the per-call stdout redirect unsafe, as it mutates a global that overlapping calls can restore out of order, so that becomes a single redirect for the life of the server, entered inside the stdio transport once it has taken stdout for the protocol writer. anyio is imported where it is used, since kcidev.main imports every subcommand at startup and anyio comes only with the mcp extra. Signed-off-by: Ben Copeland <ben.copeland@linaro.org>
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FastMCP awaits an async tool but calls a sync one inline on the event loop. Every tool here is sync and makes a blocking request, so calls were serialised across all sessions: measured against a running server, a trivial list_trees took 58.66s instead of 0.14s while one slow call was in flight.
Register an async wrapper that hands the call to a worker thread. The dashboard tools funnel through one registration site and inherit this; the Maestro tools are wrapped individually, so a new one needs the decorator adding.
Concurrency also makes the per-call stdout redirect unsafe, as it mutates a global that overlapping calls can restore out of order, so that becomes a single redirect for the life of the server, entered inside the stdio transport once it has taken stdout for the protocol writer. anyio is imported where it is used, since kcidev.main imports every subcommand at startup and anyio comes only with the mcp extra.