fix: handle outputSchema compilation errors in MCP tool discovery#21519
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claygeo wants to merge 1 commit intoanomalyco:devfrom
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fix: handle outputSchema compilation errors in MCP tool discovery#21519claygeo wants to merge 1 commit intoanomalyco:devfrom
claygeo wants to merge 1 commit intoanomalyco:devfrom
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When an MCP server returns outputSchema in its tools/list response, the SDK's default AjvJsonSchemaValidator can throw during schema compilation, causing listTools() to fail entirely. This makes the server show "Failed to get tools" even though the tools themselves are valid. opencode doesn't use output schemas (only inputSchema is read in convertMcpTool), so validation failures should be non-fatal. Wrap AjvJsonSchemaValidator with a TolerantJsonSchemaValidator that catches compilation errors and returns a permissive fallback. Pass it to both Client constructors via the SDK's jsonSchemaValidator option. Closes anomalyco#21373
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Summary
When an MCP server returns
outputSchemain itstools/listresponse, the SDK's defaultAjvJsonSchemaValidatorcan throw during schema compilation viaajv.compile(). This error propagates throughlistTools()→cacheToolMetadata(), causing opencode'sdefs()function to catch the error and returnundefined, which results in the server being marked as "Failed to get tools".opencode doesn't use output schemas at all — only
inputSchemais read inconvertMcpTool(). So validation failures onoutputSchemashould never prevent tool discovery.Fix: Create a
TolerantJsonSchemaValidatorthat wrapsAjvJsonSchemaValidatorwith try/catch ingetValidator(). On compilation failure, returns a permissive fallback validator. Pass it to bothnew Client()calls via the SDK'sjsonSchemaValidatoroption.packages/opencode/src/mcp/index.tsTest plan
tsc --noEmit)Clientconstructor correctly receives custom validator (verified via SDK source)Closes #21373