ultrawork

Orchestrates parallel subagent execution lanes with acceptance criteria and lightweight verification evidence.

10|1|Updated Jul 7, 2026
One-click install
npx skills add https://github.com/catalystctl/catcode --skill ultrawork-catalystctl
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: ultrawork
Source: https://github.com/catalystctl/catcode/tree/main/.catalyst-code/skills/ultrawork
Command: npx skills add https://github.com/catalystctl/catcode --skill ultrawork-catalystctl

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve? Sequential execution wastes turns when independent work slices could run at the same time, and unstructured delegation produces subagents that guess at intent without clear pass/fail targets. Ultrawork provides an in-session parallel execution discipline: ground context first, define acceptance criteria before launching lanes, fan out independent work to subagents, and close with concrete evidence instead of unverified claims. ## Core Features & Use Cases - Parallel lane orchestration: Fire independent subagent tasks in a single parallel call with explicit concurrency, model selection, and worktree isolation for colliding writes. - Agent tier guidance: A bundled reference maps work slices to builtin agents (scout, researcher, worker, reviewer, planner, oracle) by LOW/STANDARD/THOROUGH tiers. - Acceptance-first execution: Requires pass/fail criteria, diagnostics, and affected tests before completion is claimed, keeping verification lightweight but real. - Use Case: You need to fix a bug in a core module while also mapping regression coverage. Ultrawork keeps the coupled edit on the parent thread while a reviewer subagent runs as a parallel evidence lane, then closes with diagnostics and test output. ## Quick Start Ask the agent to run the ultrawork skill on your task, for example by saying "use ultrawork to fix the parser bug and review the changes in parallel".

Frequently Asked Questions about ultrawork

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I run coding tasks in parallel with subagents?

Define acceptance criteria first, then fire independent subagent tasks in a single parallel call with concurrency set to the batch size. Pass the model explicitly on every call, and use worktree isolation when parallel writes might collide on the same files.

When should I use ultrawork instead of a goal mode?

Use ultrawork for single-turn or short parallel execution with lightweight verification. Choose goal mode or Control Center when you need durable plans, resume across steps, deploy caps, or certified completion with self-review loops.

Which subagent should I pick for a task slice?

Match the slice to a tier: scout or researcher for read-only evidence, worker for bounded independent implementation, and reviewer, planner, or oracle for analysis and review. Keep shared-file edits on the parent thread rather than delegating them.

Why do subagent calls fail with 403 errors?

Subagent calls fail when the model parameter is omitted, because some API keys reject the implicit default model. Always pass the session's active model explicitly on every subagent invocation.

What are the limits of ultrawork parallel execution?

The soft default maximum is 8 parallel tasks with a default concurrency of 4, and an absolute safety cap of 256. Ultrawork only provides lightweight verification and does not offer persistence, certified completion, or cross-session resume.