fix(triage): harden JSON parsing against model preamble in parseDecisions#165
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…ions Extract the JSON array by finding the outermost `[` and `]` before calling JSON.parse, so conversational preamble emitted by the model no longer causes a SyntaxError. Falls back to the full string (and the original error) when no brackets are present. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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[Baton Reviewer] [must] The bracket scanner can still misparse or fail on bracket characters inside prose or JSON string values. A preamble like |
keinstn
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Jun 24, 2026
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The indexOf/lastIndexOf bracket extraction has two confirmed misfire cases and one silent-wrong-data regression. The core issue is that character-level bracket scanning cannot distinguish JSON delimiters from brackets in natural-language prose (issue refs like [#42], markdown, etc.). See inline comments for specifics.
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keinstn
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Jun 24, 2026
…isfires Replace the indexOf/lastIndexOf bracket extraction with a balanced-bracket scanner that tries each outermost [...] candidate in order, returning the first one that parses as valid JSON. Also try JSON.parse on the full clean string first so well-formed output skips extraction entirely. Adds tests covering preamble containing '[' and postamble containing ']', both of which the original indexOf/lastIndexOf approach misfired on. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
keinstn
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Jun 24, 2026
…actJsonArray Brackets inside JSON string values (e.g. `"reason": "] edge case"`) could cause the depth counter to hit zero prematurely, making the scanner return a bad substring rather than the full decisions array. Fix by tracking quoted-string and escape state so brackets inside strings are ignored. Also require each candidate to be an array of objects (not scalars), so a preamble like "See [1,2]" is not mistaken for the decisions array. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Fixes #161
Summary
parseDecisionsinscripts/triage/parse.tsnow extracts the JSON array by finding the outermost[and]before callingJSON.parse, so any conversational preamble emitted by the model (e.g. "I'll check each issue...") no longer causes aSyntaxErrorJSON.parseerror message for non-JSON responsestest/triage-parse.test.tswith unit tests covering bare JSON, preamble, preamble+postamble, code-fenced preamble, no-JSON, non-array, and invalid field casesTest plan
npm run test— 347 tests pass (29 test files)npm run typecheck— no errorsnpm run lint— no errorsparseDecisions("I'll check each issue.\n[{...}]")parses successfullyparseDecisions("no json here")still throwsSyntaxError🤖 Generated with Claude Code