Official skill · AI practice
Harness spec for an AI agent
Writes a one-page harness for an AI agent before it runs: done test, tools and limits, progress notes, small steps, stop rules, human approvals, and logs. Use it when you're about to let an AI agent run a multi-step job on its own.
AI skill
Have your AI write the rules an AI agent runs by
14 days free · No card needed
Works in Claude, ChatGPT, and coding agents. On Team and Business, the official skill in your pod updates itself when we improve it.
When to use it
- You're about to let an AI agent run a multi-step job on its own
- An agent drifts, loops, forgets its work or stops too early
What you give it
- The job and who asked for it
- The tools and systems it would touch
- What done looks like
- What must never happen
What you get
A one-page spec: goal, pass/fail done list, tools with limits, memory files, step loop, stop rules, approvals, log, and a pilot.
How it works
- Write the goal and the done test
- List the tools and their limits
- Set the memory files
- Make it work in small steps
- Write the stop rules
- Mark the human gates
- Decide what gets logged
- Run a short pilot
Example
What you give it
We want an agent to update the 40 product pages on our Shopify store from the new supplier price sheet, and email the supplier if a product is missing from the sheet. I'm the ops lead; I can check it for 15 minutes a day.
What you get back (the start of it)
Harness spec: price sheet updater
Goal: Every product page shows the supplier's new price from the November sheet. · Owner: Ops lead · Asked by: Ops lead
Done when
1. Each of the 40 products has the sheet's price on its page (one line per product in done-list.md). 2. Each product missing from the sheet is listed in missing.md with its SKU.
Tools
| Tool | Used for | Read/Write | Limit |
|---|---|---|---|
| Spreadsheet | Read the November price sheet | Read | That one file |
| Shopify | Update a product's price | Write | Price field only; no other fields |
| Draft a note to the supplier | Write | Drafts only; never sends |
The rest of this output, the full steps and the checks the AI runs before it answers are in your pod once you add the skill.
Use this skill in your AIShare it with your team
Add it to an AI Skill Pod and everyone on the team, contractors included, uses the same version from their own AI. Read the best ways to share AI skills with a team
Changelog
- v1.0.0 · · First release.
Sources
- Effective harnesses for long-running agents - Anthropic (read 2026-11-04)
- Building effective AI agents - Anthropic (read 2026-11-04)
- Demystifying evals for AI agents - Anthropic (read 2026-11-04)