Yeachan-Heo/oh-my-codex · error · Error

autoresearch candidate artifact must be a JSON object

Error message

autoresearch candidate artifact must be a JSON object

What it means

After successful JSON parsing, parseAutoresearchCandidateArtifact requires the top-level value to be a non-null, non-array object. Arrays, strings, numbers, booleans, or null are rejected before field checks run.

Source

Thrown at src/autoresearch/runtime.ts:1028

    latestEvaluatorFile: manifest.latest_evaluator_file,
    resultsFile: manifest.results_file,
    stateFile: activeRunStateFile(projectRoot),
    candidateFile: manifest.candidate_file,
    repoRoot: manifest.repo_root,
    worktreePath: manifest.worktree_path,
    taskDescription: `autoresearch resume ${runId}`,
  };
}

export function parseAutoresearchCandidateArtifact(raw: string): AutoresearchCandidateArtifact {
  let parsed: unknown;
  try {
    parsed = JSON.parse(raw);
  } catch {
    throw new Error('autoresearch candidate artifact must be valid JSON');
  }
  if (!parsed || typeof parsed !== 'object' || Array.isArray(parsed)) {
    throw new Error('autoresearch candidate artifact must be a JSON object');
  }
  const record = parsed as Record<string, unknown>;
  const status = record.status;
  if (status !== 'candidate' && status !== 'noop' && status !== 'abort' && status !== 'interrupted') {
    throw new Error('autoresearch candidate artifact status must be candidate|noop|abort|interrupted');
  }
  if (record.candidate_commit !== null && typeof record.candidate_commit !== 'string') {
    throw new Error('autoresearch candidate artifact candidate_commit must be string|null');
  }
  if (typeof record.base_commit !== 'string' || !record.base_commit.trim()) {
    throw new Error('autoresearch candidate artifact base_commit is required');
  }
  if (typeof record.description !== 'string') {
    throw new Error('autoresearch candidate artifact description is required');
  }
  if (!Array.isArray(record.notes) || record.notes.some((note) => typeof note !== 'string')) {
    throw new Error('autoresearch candidate artifact notes must be a string array');
  }

View on GitHub (pinned to 3ad79a8a6f)

Solutions

  1. Ensure the worker writes a single JSON object ({...}) as the artifact root
  2. If double-serialized (artifact is a JSON string containing JSON), parse once more before handing it over
  3. If the worker emits an array, wrap it in an object (e.g. { results: [...] }) to satisfy the contract
  4. Add a pre-check with JSON.parse + typeof === 'object' in your harness to fail fast with better context

Example fix

// before
const artifact = parseAutoresearchCandidateArtifact('"{\\\"status\\\":\\\"candidate\\\"}"'); // parses to a string
// after
const artifact = parseAutoresearchCandidateArtifact('{"status":"candidate",...}');
Defensive patterns

Strategy: type-guard

Validate before calling

const parsed = parseJsonSafe(raw);
if (typeof parsed !== 'object' || parsed === null || Array.isArray(parsed)) {
  throw new Error('Candidate artifact root must be a JSON object.');
}

Type guard

function isJsonObject(v: unknown): v is Record<string, unknown> {
  return typeof v === 'object' && v !== null && !Array.isArray(v);
}

Try / catch

try { const a = parseAutoresearchCandidateArtifact(raw); }
catch (e) { if (e instanceof Error && e.message === 'autoresearch candidate artifact must be a JSON object') { /* fix double serialization or array wrapping in worker output */ } throw e; }

Prevention

When it happens

Trigger: Passing a JSON artifact that parses to a primitive or array — e.g. a worker emitting a bare string, a JSON array of notes, or 'null' as the whole document.

Common situations: Workers wrapping the artifact in an array, emitting a quoted JSON string of the real object (double serialization), or defaulting to null/empty output on failure paths.

Related errors

AI-assisted analysis of Yeachan-Heo/oh-my-codex@3ad79a8a6f (2026-08-27). Data as JSON: /api/errors/6a5c4a19bcc0ecd8. Report an issue: GitHub.