How do I install the Ucp Checkout skill?

Run npx skillmds@latest add viryazheng/ucp-checkout in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Ucp Checkout safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Ucp Checkout?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Ucp Checkout free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Ucp Checkout?

ViryaZheng (@viryazheng) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Ucp Checkout by viryazheng — Agent Skill

Name: Ucp Checkout
Author: ViryaZheng

Ucp Checkout

Generates or guides a sandbox Python FastAPI UCP shopping checkout server from ucp-profile.json and catalog.json. Use after ucp-profile and ucp-catalog are complete to create catalog search/lookup and checkout create/retrieve/update/ cancel endpoints for local preflight validation.

ViryaZheng b2af488 4 files · 10.9 KB Updated Sep 17, 2026

File contents

UCP Checkout

Generate a sandbox FastAPI server for UCP catalog and checkout preflight.

Required Inputs

store/clients/{client_name}/ucp-profile.json
store/clients/{client_name}/catalog.json

Generate

python ${CLAUDE_SKILL_DIR}/scripts/generate_api.py \
  --profile store/clients/{client}/ucp-profile.json \
  --catalog store/clients/{client}/catalog.json \
  --output-dir store/clients/{client}/ucp-server

Use --force only when intentionally replacing an existing generated server.

Generated Endpoints

GET  /.well-known/ucp
POST /ucp/v1/catalog/search
POST /ucp/v1/catalog/lookup
POST /ucp/v1/checkout
GET  /ucp/v1/checkout/{id}
POST /ucp/v1/checkout/{id}
POST /ucp/v1/checkout/{id}/cancel

Validate Locally

cd store/clients/{client}/ucp-server
pip install -r requirements.txt
uvicorn app.main:app --port 8000

python ${CLAUDE_SKILL_DIR}/../ucp-validate/scripts/validate_ucp.py \
  http://localhost:8000 \
  --runtime-endpoint http://localhost:8000/ucp/v1

Hard Rules

Generated code is sandbox-only.
Do not implement real payment capture in generated output.
Never call checkout completion during automated validation.
Keep secrets out of ucp-profile.json and generated sample data.

Read references/checkout-lifecycle.md for lifecycle and totals rules.

Frequently asked questions