tinyhumansai/openhuman · error · SpecError

duplicate branch "${agent.branch}"

Error message

duplicate branch "${agent.branch}"

What it means

Branch strings must be unique across the batch — the seenBranch Set rejects a second agent declaring the same branch, with the duplicated value and path "agents[i].branch". Uniqueness matters because each agent's work is pushed to its own git branch; two agents sharing one would clobber each other. Given the id/issue cross-checks, this usually means fully duplicated entries.

Source

Thrown at scripts/agent-batch/lib.mjs:136

      throw new SpecError(
        `branch must match cursor/<id>-<issue>-<slug> (got "${agent.branch}")`,
        `${at}.branch`,
      );
    }
    if (m[1] !== agent.id) {
      throw new SpecError(
        `branch id segment "${m[1]}" does not match agent id "${agent.id}"`,
        `${at}.branch`,
      );
    }
    if (Number(m[2]) !== agent.issue) {
      throw new SpecError(
        `branch issue segment "${m[2]}" does not match agent issue ${agent.issue}`,
        `${at}.branch`,
      );
    }
    if (seenBranch.has(agent.branch)) {
      throw new SpecError(`duplicate branch "${agent.branch}"`, `${at}.branch`);
    }
    seenBranch.add(agent.branch);
    if (!Array.isArray(agent.owned_paths) || agent.owned_paths.length === 0) {
      throw new SpecError(
        "owned_paths must be a non-empty array",
        `${at}.owned_paths`,
      );
    }
    for (let j = 0; j < agent.owned_paths.length; j++) {
      const p = agent.owned_paths[j];
      if (typeof p !== "string" || p.length === 0) {
        throw new SpecError(
          "must be a non-empty string",
          `${at}.owned_paths[${j}]`,
        );
      }
      if (p.includes("*") || p.includes("?")) {
        throw new SpecError(

View on GitHub (pinned to a221052e0d)

Solutions

1. Make each branch unique by construction: cursor/<id>-<issue>-<slug> with that agent's own id and issue
2. Since id and issue are already forced unique, a duplicate branch almost always means the branch was not regenerated after fixing those fields — regenerate it
3. Check: new Set(agents.map(a => a.branch)).size === agents.length

Example fix

// before
{ "id": "a01", "issue": 5312, "branch": "cursor/a01-5312-shared-slug" }
{ "id": "a02", "issue": 5313, "branch": "cursor/a01-5312-shared-slug" }

// after
{ "id": "a01", "issue": 5312, "branch": "cursor/a01-5312-fix-ci-timeout" }
{ "id": "a02", "issue": 5313, "branch": "cursor/a02-5313-tighten-lint" }

const branches = spec.agents.map((a) => a.branch);
if (new Set(branches).size !== branches.length) {
  console.error("duplicate branch names across agents");
  process.exit(1);
}

try {
  validateSpec(spec);
} catch (e) {
  if (e instanceof SpecError && /duplicate branch/.test(e.message)) {
    console.error(`regenerate the copied branch: ${e.message}`);
    process.exit(1);
  }
  throw e;
}

When it happens

Trigger: Two agents with identical branch strings — typically a whole duplicated agent entry where id/issue checks were fixed to be distinct but the branch slug was left identical, or the same agent pasted twice with only cosmetic edits.

Common situations: Copy-paste growth of a spec where branches were templated as cursor/a01-5312-... and never varied; merge of two spec files that both contain an agent with the same branch.

Related errors

• base_branch must be "main" (got "${spec.base_branch}")
• duplicate id "${agent.id}"
• duplicate issue #${agent.issue}
• branch must match cursor/<id>-<issue>-<slug> (got "${agent.b
• batch_id must be a kebab-case slug

AI-assisted analysis of tinyhumansai/openhuman@a221052e0d (2026-08-16). Data as JSON: /api/errors/17c15b7e4ddfe3e2. Report an issue: GitHub.