fix(web): warm lancedb at startup to fix first-run MCP bootstrap_failure#33
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jeanbrazeau wants to merge 1 commit into
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fix(web): warm lancedb at startup to fix first-run MCP bootstrap_failure#33jeanbrazeau wants to merge 1 commit into
jeanbrazeau wants to merge 1 commit into
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On a cold server the first lazy `import lancedb` (koan/memory/retrieval/index.py)
runs synchronously on the asyncio event loop during the first run. The
seconds-long native import blocks the loop in the exact window where a
freshly-spawned agent's CLI fetches tools/list from koan's MCP server. The
response never arrives, so the agent starts with no koan tools, never calls
koan_complete_step, and the run dies with bootstrap_failure ("Process exited
before first koan_complete_step call"). Subsequent runs were fine because
lancedb was already warm.
Warm koan.memory.retrieval.index in the server lifespan, off-loop via
asyncio.to_thread, before the server accepts any run. Best-effort: a warmup
failure is logged at debug and never blocks startup.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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On a cold server the first lazy
import lancedb(koan/memory/retrieval/index.py) runs synchronously on the asyncio event loop during the first run. The seconds-long native import blocks the loop in the exact window where a freshly-spawned agent's CLI fetches tools/list from koan's MCP server. The response never arrives, so the agent starts with no koan tools, never calls koan_complete_step, and the run dies with bootstrap_failure ("Process exited before first koan_complete_step call"). Subsequent runs were fine because lancedb was already warm.Warm koan.memory.retrieval.index in the server lifespan, off-loop via asyncio.to_thread, before the server accepts any run. Best-effort: a warmup failure is logged at debug and never blocks startup.