ucp-conformance

Testing & Quality

Run and write UCP conformance tests — validate a UCP implementation against the official test suite covering checkout lifecycle, orders, fulfillment, payments, idempotency, webhooks, and security. Use when testing or validating a UCP implementation.

QUICK START

How to use this skill

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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/majiayu000/claude-skill-registry/blob/HEAD/skills/testing/ucp-conformance/SKILL.md

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UCP Conformance Testing

Before running tests

Fetch the latest test suite: Web-search github Universal-Commerce-Protocol conformance and fetch the README for current setup instructions, test data format, and CLI flags.

Repository: https://github.com/Universal-Commerce-Protocol/conformance

Conceptual Architecture

What the Conformance Suite Tests

The official suite contains ~13 test files covering:

Test File	What It Validates
Checkout lifecycle	Full create → update → complete → verify flow
Order management	Order creation, status transitions, data integrity
Fulfillment	Shipping/pickup methods, group selection, option validation
Card credentials	Payment credential format, tokenization
Webhooks	Delivery, retry, signature verification
Idempotency	Duplicate request handling, cache behavior
Invalid input	Error responses for malformed requests
Protocol compliance	Headers, TLS, version negotiation
Data validation	Schema compliance, required fields, type correctness
Service bindings	REST/MCP/A2A transport correctness
Business logic	Totals calculation, tax, discount application
AP2 integration	Mandate generation, signing, verification
Security (simulation URLs)	URL validation, injection prevention

How to Run

Clone the conformance repo
Install dependencies with uv sync
Start your UCP server locally
Run tests pointing at your server:

uv run checkout_lifecycle_test.py \
  --server_url=http://localhost:8182 \
  --simulation_secret=your-secret \
  --conformance_input=test_data/your_store/conformance_input.json

Test Data

Tests require a conformance_input.json file that describes your store's products, prices, and expected behaviors. Check the sample test data in the repo for the format.

Writing Custom Conformance Tests

When extending UCP with custom capabilities:

Use the same test patterns as the official suite
Test capability negotiation (extension present/absent)
Test schema validation against your custom schemas
Test error cases specific to your extension
Test idempotency for all mutating operations

Integration with CI/CD

Run conformance tests as part of your CI pipeline
Use the --server_url flag to point at staging environments
Track test pass rates as a quality gate for deployments

Always fetch the latest test suite before running — new tests are added as the spec evolves.