Build with an AI agent

mongrl is built to be built on by coding agents. Everything an agent needs is machine-readable, in one place, and kept in sync with the API by the build.

What to give your agent

Resource	Use it for
/llms.txt	The entry point: what mongrl is, the rules, and links to every page as Markdown.
/llms-full.txt	Every guide and the full API reference in one file, for agents with a big context.
/llms-small.txt	The same, trimmed, for smaller contexts.
/openapi.json	The public API spec. Generate the client from it.
/AGENTS.md	Rules to keep in the storefront repo, so every session follows them.
Any page + .md	One topic as Markdown, e.g. /guides/checkout.md.

Set up the repo

curl -o AGENTS.md https://dev.mongrl.com/AGENTS.md
curl -o openapi.json https://dev.mongrl.com/openapi.json

If your agent reads CLAUDE.md rather than AGENTS.md, add a CLAUDE.md that says @AGENTS.md.

Then put the keys in your environment, never in the repo:

MONGRL_API_URL=https://api.staging.mongrl.com
MONGRL_SECRET_KEY=sk_test_…
STRIPE_PUBLISHABLE_KEY=pk_test_…   # the marketplace's Stripe account

A first prompt

Read https://dev.mongrl.com/llms.txt and AGENTS.md. We're building the storefront
for our marketplace on mongrl, with <your stack, e.g. TanStack Start / Next.js>.

1. Generate a typed client from openapi.json with @hey-api/openapi-ts.
2. Add a server-only mongrl client (secret key from MONGRL_SECRET_KEY, the
   user's session from an HttpOnly cookie as X-User-Session).
3. Build the shop page: search with q, category and brand filters, sort, and
   cursor paging, showing display_price in the visitor's currency.
4. Build the listing page from getListing.

Use only endpoints and fields from openapi.json. Show problem `detail`s from
errors to people. Stop and show me the shop page before going further.

Then go area by area, one guide per step, so the agent loads only what it needs:

1. Accounts: “Follow https://dev.mongrl.com/guides/accounts.md: sign-up, sign-in with password and with emailed links, confirm email, reset password.”
2. Checkout: “Follow https://dev.mongrl.com/guides/checkout.md and https://dev.mongrl.com/guides/delivery.md.”
3. Selling: “Follow https://dev.mongrl.com/guides/selling.md and https://dev.mongrl.com/guides/payouts.md.”
4. Messages and the pages emails link to: “Follow https://dev.mongrl.com/guides/messages.md and https://dev.mongrl.com/guides/storefront-pages.md.”

Why agents get it right here

• One spec, generated from code. The spec on this site is built from the API’s own code on every release. An agent coding against it codes against what the API does.
• Types, not guesses. With a generated client, a wrong field or path fails to compile instead of failing in production.
• Errors that say how to fix them. Validation errors name the field (body.price.amount) and the problem, so an agent can correct its own request.
• Safe retries. Idempotency keys make a repeated write run once, so an agent (or a flaky network) can’t buy twice.
• Test keys. sk_test_… keys and Stripe test cards let an agent run the whole flow without touching real orders or money.