# Set up with an agent (https://docs.owndiff.com/agent-setup)

Install the GitHub App first ([Quickstart](/quickstart)). Then open your coding agent in the repository and paste this prompt:

```text title="Prompt"
Set up owndiff in this repository.

1. Read https://docs.owndiff.com/llms-full.txt. It is the source of truth
   for owndiff.json and the .owndiff/ folder.
2. Explore the repository: any existing owndiff.json and .owndiff/, the
   README, docs, ADRs, PRDs and specs, and the main product areas in the
   code.
3. Write only what owndiff can't find by itself:
   - owndiff.json, only if it is needed: `context` when docs live outside
     the default paths, `ignore` for generated code, `areas` only when the
     code structure doesn't show them.
   - .owndiff/<topic>.md for business rules you found in code or docs that
     are not written down anywhere else: prices, plan limits, roles,
     legal requirements. One topic per file, short and in plain language.
   - .owndiff/<flow>.md for the main user flows that no PRD or spec
     describes: a user story with acceptance criteria, scoped with
     `include` to the code of that flow.
   - Don't copy existing docs into .owndiff/. owndiff reads them in place.
4. Add `check: true` only for rules whose breach should get its own check
   run, and ask me before you do.
5. Open a pull request with the configuration. List every rule you wrote
   down and the file or code you took it from.
```

## What the agent does [#what-the-agent-does]

The agent writes as little as it can. owndiff already reads your README, `docs/`, ADRs and PRDs, so the useful work is the rules nobody wrote down: a free plan limit hard-coded in a constant, an invoice that must never change after it is issued, a role only admins may grant.

You review its pull request like any other. That pull request changes the rules owndiff reviews with, so owndiff marks it as a product decision: it is never **Aligned** until someone records the decision.

## Why a prompt and not a button [#why-a-prompt-and-not-a-button]

owndiff is read-only on GitHub. It never writes to your repository, which keeps the app easy to approve in a security review. Your agent already has write access, works in your branch and opens a pull request your team reviews.

## Keeping it current [#keeping-it-current]

Run the same prompt again when the product changes a lot, for example after a new pricing model or a new area. The agent reads the current `.owndiff/` first and updates it instead of starting over.