fix(web,mcp): gracefully degrade when MCP loading fails in Web UI worker#1816
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AI-fullcup wants to merge 1 commit intoMoonshotAI:mainfrom
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fix(web,mcp): gracefully degrade when MCP loading fails in Web UI worker#1816AI-fullcup wants to merge 1 commit intoMoonshotAI:mainfrom
AI-fullcup wants to merge 1 commit intoMoonshotAI:mainfrom
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When an MCP server fails to connect (e.g., due to a port conflict), the Web UI session worker previously crashed entirely, causing messages to get stuck in thinking state indefinitely. Changes: - In `_agent_loop()`, catch `MCPRuntimeError` during `wait_for_background_mcp_loading()` and log a warning instead of letting the exception crash the agent loop. - In `_read_loop()`, when an unexpected exception occurs, clear `_in_flight_prompt_ids` and emit an error status so the frontend can recover instead of leaving prompts stuck in thinking state. Fixes MoonshotAI#1766
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Problem
When an MCP server fails to connect (e.g., due to a port conflict when switching from TUI to Web UI), the Web UI session worker crashes entirely. This causes messages to get stuck in the "thinking" state indefinitely, and the frontend becomes unresponsive.
This is described in detail in #1766.
Root Cause
In
kimi_cli/soul/kimisoul.py,_agent_loop()callswait_for_background_mcp_loading()inside atry/finallyblock. Thefinallyonly ensuresMCPLoadingEndis sent, but does not catchMCPRuntimeError. The exception bubbles up and crashes the agent loop.In
kimi_cli/web/runner/process.py,_read_loop()catches unexpected exceptions but:_in_flight_prompt_ids"error"or"idle"status to WebSocketsChanges
src/kimi_cli/soul/kimisoul.py:MCPRuntimeErrorMCPRuntimeErrorduringwait_for_background_mcp_loading()and log a warning, allowing the conversation to continue without MCP tools.src/kimi_cli/web/runner/process.py:_read_loop(), clear_in_flight_prompt_idsand emit an"error"status so the frontend can recover instead of leaving prompts stuck in "thinking".Testing
py_compileFixes #1766