API Contract Until Match

Loop until API responses match the OpenAPI or JSON Schema contract — catch drift between docs and implementation.

3 copies · 7 views

Use loop copies the kickoff. Share copies the loop link. Open in Cursor / Claude Code only pre-fill that prompt — they do not install hook files. Download loop saves a README and kickoff into .cursor/loops/api-contract-until-match/ — no hooks required. Full install guide

Guardrails

Hardened

Anti-gaming rules

Rules the agent must follow so it cannot cheat the exit condition.

Do not modify the check command or exit criteria to force success
Do not skip, disable, or bypass checks to pass the exit condition
If stuck after several iterations, stop and report blockers instead of gaming metrics

How to run this loop

Prompt only

Run “API Contract Until Match” in your agent

Deeplinks and “Open in Cursor” only paste the kickoff prompt. They do not install hook files — your agent cannot tell whether files are on disk until you add them yourself.

Two separate pieces

Kickoff prompt — tells the agent the goal, check command, exit condition, and how to self-pace between passes.

1
Copy or open the kickoff prompt
Click Use loop to copy the kickoff into your clipboard. Open in Cursor and Open in Claude Code only open the agent with that prompt — they do not configure automation for you.
2
Paste into your coding agent
Start a chat in Cursor, Claude Code, Codex, or any agent. Paste the kickoff. The prompt includes the goal, iteration limit, shell check, and first step.
3
Agent self-paces until done
The agent runs the loop: act → run check command → read output → repeat until the exit condition is met or max iterations is reached. No install step is required for prompt-only loops.

Full guide with Cursor /loop notes: How to install loops

manual trigger

API

Manual start

Run contract tests

Fix implementation or spec

All API contract tests pass

Rendering diagram…

Steps

What the agent does on each pass.

1. Run contract tests

Run contract tests against openapi.yaml or schema fixtures. List every mismatch with endpoint and field.

npm run test:contract

2. Fix implementation or spec

Fix the smallest change: update handler types/validation or correct the spec if the code is canonical.

Kickoff prompt

Copy this into your coding agent to start the loop.

Start the "API Contract Until Match" loop.

Goal: API implementation matches the published contract
Max iterations: 10
Between iterations run: npm run test:contract
Exit when: contract test suite exits 0

Step 1: Run contract tests. Fix each schema/response mismatch with minimal diffs, then re-run.

Self-pace this loop. After each iteration, run the check command, read the output, and only continue if the exit condition is not met. Stop when the exit condition passes or max iterations is reached. Give a short status update each pass.

Related loops

API

manual

2 copies

OpenAPI Sync Until Valid

Keep openapi.yaml valid and in sync with route handlers — lint the spec and fix drift each pass.

Start the "OpenAPI Sync Until Valid" loop. Goal: openapi.yaml lints clean and matches implemented routes Max iterations: 8 Between iterations run: npx @redocly/cli lint openapi.yaml Exit when: OpenAPI lint exits 0 Step 1: Lint openapi.yaml. Fix spec errors and handler drift until lint passes. Self-pace this loop. After each iteration, run the check command, read the output, and only continue if the exit condition is not met. Stop when the exit condition passes or max iterations is reached. Give a short status update each pass.

api

openapi

docs

by loops!

View