fix(mastra): keep replay conversion alive on malformed tool-call arguments - #2576
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fix(mastra): keep replay conversion alive on malformed tool-call arguments#2576jstar0 wants to merge 1 commit into
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…ments Replay history can carry concatenated or invalid tool-call argument strings. A bare JSON.parse threw and made every later run on that thread fail before reaching the model. Recover the first JSON value when arguments are concatenated, skip a tool-call that still cannot be parsed, and leave the rest of the history runnable. Fixes ag-ui-protocol#2568 Signed-off-by: King Star <mcxin.y@gmail.com>
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Fixes #2568
Summary
convertAGUIMessagesToMastraparsed replayed tool-callargumentswith a bareJSON.parse. After concurrent runs leave concatenated JSON in in-memory history ({"mine":true}{"mine":true}), every lateragent/runon that thread throws before reaching the model, so the thread stays unrunnable until process restart.On parse failure the converter now recovers the first complete JSON object or array when the rest is trailing concatenation, and skips a tool-call that still cannot be parsed. The rest of the history continues through conversion. Valid JSON is unchanged.
This is the robustness half of #2568. It does not claim to fix the unisolated concurrency path that writes concatenated arguments into process memory.
Verification
integrations/mastra/typescript/src/__tests__/message-conversion.test.tscover concatenated objects (including a}inside a string), skipping irreparable arguments while keeping a sibling tool-call, and empty arguments becoming{}.pnpm --filter @ag-ui/mastra test— 23 files / 340 tests passed (workspace@ag-ui/core,@ag-ui/client,@ag-ui/proto, and@ag-ui/a2ui-toolkitdist builds first, as usual).pnpm --filter @ag-ui/mastra typecheck— clean.