fix(mcp): retry listTools() before evicting client on transient failure#17153
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nil957 wants to merge 1 commit intoanomalyco:devfrom
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fix(mcp): retry listTools() before evicting client on transient failure#17153nil957 wants to merge 1 commit intoanomalyco:devfrom
nil957 wants to merge 1 commit intoanomalyco:devfrom
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Previously, a single transient listTools() failure (timeout, pipe hiccup, GC pause) would permanently delete the MCP client from the session state with no retry or reconnection mechanism. This caused MCP tools to silently vanish mid-session while the server process was still running. This commit: 1. Adds retry logic (3 attempts with 1s delay) before marking a client as failed 2. Removes the immediate 'delete s.clients[clientName]' that permanently evicted healthy servers on transient errors 3. Logs retry attempts at warn level for visibility The client remains in 'failed' status after all retries are exhausted, but is no longer deleted, allowing future state() calls to attempt reconnection. Fixes anomalyco#17099
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Issue for this PR
Closes #17099
Type of change
What does this PR do?
This PR fixes a critical bug where MCP tools silently vanish mid-session after a single transient
listTools()failure.The Problem:
In
mcp/index.ts, whenclient.listTools()fails (timeout, pipe hiccup, GC pause), the code immediately executesdelete s.clients[clientName], permanently removing the client from the singleton state. The MCP server process may still be running perfectly fine, but the tools are gone forever until OpenCode restarts.The Fix:
delete s.clients[clientName]that permanently evicted healthy serversWhy it works:
Transient failures (network blips, GC pauses, brief timeouts) are common in long-running sessions. Retrying gives the MCP server a chance to respond before we give up. Not deleting the client allows future reconnection attempts.
How did you verify your code works?
Screenshots / recordings
N/A - backend change
Checklist