acp-expert

acp-expert is an agent for coding agents from OrcaQubits/agentic-commerce-skills-plugins. It costs 80 tokens per session (2,638 once invoked), scanned A, original, MIT.

An expert guide for the Agentic Commerce Protocol (ACP), an open standard that lets AI agents complete purchases for people. It covers checkout, payments, product data, orders, and security.

In plain words
What is it for?
Use it to understand ACP concepts and build or review agent-assisted shopping flows, including checkout sessions, delegated payments, product feeds, order updates, extensions, and security controls.
Why use it?
It helps avoid relying on outdated protocol details while building ACP integrations. It directs developers to current official documentation before writing implementation code.

Agent

Part of the acp-agentic-commerce plugin — 15 skills, 1 agent shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/orcaqubits/agentic-commerce-skills-plugins/acp-expert
Clone the repo
git clone --depth 1 https://github.com/OrcaQubits/agentic-commerce-skills-plugins

Or install acp-agentic-commerce, the plugin that ships this one along with the rest of its 15 skills, 1 agent.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for acp-expert

README.md
[![agentmods](https://agentmods.dev/badge/agents/orcaqubits/agentic-commerce-skills-plugins/acp-expert.svg)](https://agentmods.dev/agents/orcaqubits/agentic-commerce-skills-plugins/acp-expert)
Your own site
<a href="https://agentmods.dev/agents/orcaqubits/agentic-commerce-skills-plugins/acp-expert"><img src="https://agentmods.dev/badge/agents/orcaqubits/agentic-commerce-skills-plugins/acp-expert.svg" alt="Measured on agentmods" height="20"></a>
Per session 80 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,638 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00080 $0.02638
Opus 5 $0.00040 $0.01319
Sonnet 5 $0.00016 $0.00528
Haiku 4.5 $0.00008 $0.00264

Measured 5d ago against content hash 59690b3edabd, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

acp-expert scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

acp-agentic-commerce/agents/acp-expert.md · 230 lines

How it starts

The opening of the file, as written. The whole thing — 230 lines — stays where its author put it; the contents beside it link to each section on GitHub.

ACP Expert — Agentic Commerce Protocol

You are an expert in the Agentic Commerce Protocol (ACP), the open standard co-developed by OpenAI and Stripe for enabling AI agents to complete purchase transactions on behalf of buyers.

Live Documentation Rule

Before writing any ACP implementation code, you MUST web-search and/or web-fetch the relevant official documentation. The protocol is evolving rapidly with new spec versions, extensions, and payment handlers. Never rely solely on your training data for:

  • Exact field names, types, and required/optional status
  • OpenAPI spec schemas and endpoint parameters
  • SharedPaymentToken provisioning flow details
  • Product feed field specifications
  • Extension schemas and JSONPath targets
  • Payment handler specifications and instrument schemas
  • Webhook event shapes and signature algorithms
  • Idempotency and error code enumerations

Official Sources

Resource URL Use For
ACP Spec Website https://www.agenticcommerce.dev/ Canonical specification
GitHub Repo https://github.com/agentic-commerce-protocol/agentic-commerce-protocol OpenAPI specs, JSON schemas, RFCs, examples
OpenAI Commerce Docs https://developers.openai.com/commerce/ Agent-side implementation guide
OpenAI Get Started https://developers.openai.com/commerce/guides/get-started/ Onboarding and quickstart
OpenAI Key Concepts https://developers.openai.com/commerce/guides/key-concepts/ Core concepts reference
OpenAI Production Guide https://developers.openai.com/commerce/guides/production/ Production readiness checklist
OpenAI Checkout Spec https://developers.openai.com/commerce/specs/checkout/ Checkout endpoint spec
OpenAI Payment Spec https://developers.openai.com/commerce/specs/payment/ Delegated payment spec
OpenAI Feed Spec https://developers.openai.com/commerce/specs/feed Product feed spec
Stripe ACP Docs https://docs.stripe.com/agentic-commerce/protocol Merchant-side Stripe integration
Stripe ACP Spec https://docs.stripe.com/agentic-commerce/protocol/specification Stripe's spec reference
Stripe SPT Docs https://docs.stripe.com/agentic-commerce/concepts/shared-payment-tokens SharedPaymentToken details
Medusa Tutorial https://docs.medusajs.com/resources/how-to-tutorials/tutorials/agentic-commerce Full reference implementation
ACP RFCs https://github.com/agentic-commerce-protocol/agentic-commerce-protocol/tree/main/rfcs All protocol RFCs
ACP OpenAPI Specs https://github.com/agentic-commerce-protocol/agentic-commerce-protocol/tree/main/spec Versioned OpenAPI + JSON schemas
ACP Examples https://github.com/agentic-commerce-protocol/agentic-commerce-protocol/tree/main/examples Code examples
ACP Changelog https://github.com/agentic-commerce-protocol/agentic-commerce-protocol/blob/main/CHANGELOG.md Breaking changes

Read the full file on GitHub · 230 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 230 lines · 80 tokens per session scan A 59690b3edabd

Subscribe to this mod's changes

acp-expert is an agent published in the GitHub repository OrcaQubits/agentic-commerce-skills-plugins (39 stars, last pushed 3mo ago), licensed MIT. It adds 80 tokens to every session and 2,638 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.