coleam00/Archon · error · Error

Run id '${runId}' matches more than one run in this project:

Error message

Run id '${runId}' matches more than one run in this project:
${candidates}
Use more characters or the full id.

What it means

A short run-id prefix matched multiple runs within the resolved project, so the CLI refuses to guess and lists the candidate full ids, asking for a longer prefix.

Source

Thrown at packages/cli/src/commands/workflow.ts:4084

  if (FULL_RUN_ID_RE.test(runId)) return runId;
  if (cwd === undefined && codebaseId === undefined) {
    if (requirePrefixMatch) {
      throw new Error(`Cannot resolve run id prefix '${runId}' without a project directory.`);
    }
    return runId;
  }
  const resolvedCodebaseId =
    codebaseId ?? (cwd === undefined ? undefined : (await findCodebaseForCheckoutPath(cwd))?.id);
  if (!resolvedCodebaseId) {
    if (requirePrefixMatch) {
      throw new Error(`Cannot resolve run id prefix '${runId}' outside a registered project.`);
    }
    return runId;
  }
  const matches = await workflowDb.findWorkflowRunsByIdPrefix(runId, resolvedCodebaseId);
  if (matches.length > 1) {
    const candidates = matches.map(match => `  ${match.id}`).join('\n');
    throw new Error(
      `Run id '${runId}' matches more than one run in this project:\n${candidates}\nUse more characters or the full id.`
    );
  }
  if (matches.length === 0) {
    if (requirePrefixMatch) {
      throw new Error(`No workflow run matches prefix '${runId}' in this project.`);
    }
    return runId;
  }
  return matches[0].id;
}

/**
 * Shared `--detach` front half for `approve`/`reject`/`resume`. Validates the run
 * READ-ONLY via `precheck`, then hands the whole command to a detached child that
 * re-invokes the same argv (minus `--detach`/`--json`) and owns ALL state mutation
 * in its own process group — so killing the shell that hosted the parent cannot
 * zombie the run mid-resume. The parent must never call

View on GitHub (pinned to 0773b97458)

Solutions

Re-run with more characters of the id until it is unique.
Use the full run id copied from the run list or the candidates shown in the error.
Filter `archon workflow runs` by status/date first to find the exact id.

Example fix

// before
archon workflow get ab
// after
archon workflow get ab12cd34

Defensive patterns

Strategy: validation

Validate before calling

const runs = await listRuns({ json: true }); const hits = runs.filter(r => r.id.startsWith(prefix)); if (hits.length !== 1) throw new Error('prefix not unique, use full id');

Try / catch

try { await getRun(prefix); } catch (e) { const ids = [...String(e.message).matchAll(/\s+([0-9a-f-]{36})/g)].map(m => m[1]); if (ids.length) return getRun(ids[0]); throw e; }

Prevention

Use at least 8+ characters of the id when using prefixes.
Generate a unique prefix per run when scripting (e.g. derive from timestamped ids).
Parse the candidate list out of the error message to disambiguate programmatically.

When it happens

Trigger: `workflow get/resume/approve` with a prefix (e.g. 2-4 chars) that is a prefix of two or more run ids in the same codebase.

Common situations: Sharing a session id prefix across many runs of the same project; copying only the first few characters of an id from a log line; tab-completion habits from other tools.

Related errors

AI-assisted analysis of coleam00/Archon@0773b97458 (2026-09-01). Data as JSON: /api/errors/f20158f01c492de4. Report an issue: GitHub.