ReturnCheck

Name: ReturnCheck
Author: mangelmartinezfer-hue

by mangelmartinezfer-hueversion 1.1.0i★ –iComputer or cloud

Registry nameio.github.mangelmartinezfer-hue/returncheck

Install

Overview

Description from the maker (original English)

Can this product actually be returned? The merchant's exact clause, its URL and the date.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

User voiceiNo reviews yetReviews open together with accounts in a later step
Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
UsageiNot measured yet★ –

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Connection: Computer or cloud
Transport: stdio, Streamable HTTP
Category: Online shops & payments
You need to fill in: RETURNCHECK_API_KEY

Install

Pick the AI app you use, then copy the settings.

Before you install

Basic checks: 1 of 1 passed
Runs on the maker’s server: what you ask it goes through their server.
You fill in yourself: RETURNCHECK_API_KEY, RETURNCHECK_URL, RETURNCHECK_FETCH_LOCALLY, RETURNCHECK_TIMEOUT_MS

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

Runs in the cloudNothing to install; it connects over the internet
npmNode.js installed (for the npx command)

Which app do you use?

ClaudeClaude CodeCursorVS CodeChatGPT

Pick your app above. We remember it, so next time the button says “Install in …”.

Works in Claude on the web, desktop and mobile:

Open Settings → Connectors
Press Add custom connector
Paste the address below and press Add
If it asks you to sign in, sign in with the maker

https://returncheck.m-angelmartinez-fer.workers.dev/mcp

Or run it on your computer

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "returncheck": {
      "command": "npx",
      "args": [
        "-y",
        "returncheck-mcp"
      ],
      "env": {
        "RETURNCHECK_API_KEY": "your-value",
        "RETURNCHECK_URL": "your-value",
        "RETURNCHECK_FETCH_LOCALLY": "your-value",
        "RETURNCHECK_TIMEOUT_MS": "your-value"
      }
    }
  }
}

Run this in your terminal

claude mcp add --transport http returncheck https://returncheck.m-angelmartinez-fer.workers.dev/mcp

Or run it on your computer

claude mcp add returncheck --env RETURNCHECK_API_KEY=your-value --env RETURNCHECK_URL=your-value --env RETURNCHECK_FETCH_LOCALLY=your-value --env RETURNCHECK_TIMEOUT_MS=your-value -- npx -y returncheck-mcp

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "returncheck": {
      "url": "https://returncheck.m-angelmartinez-fer.workers.dev/mcp"
    }
  }
}

Or run it on your computer

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "returncheck": {
      "command": "npx",
      "args": [
        "-y",
        "returncheck-mcp"
      ],
      "env": {
        "RETURNCHECK_API_KEY": "your-value",
        "RETURNCHECK_URL": "your-value",
        "RETURNCHECK_FETCH_LOCALLY": "your-value",
        "RETURNCHECK_TIMEOUT_MS": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "returncheck": {
      "type": "http",
      "url": "https://returncheck.m-angelmartinez-fer.workers.dev/mcp"
    }
  }
}

Or run it on your computer

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "returncheck": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "returncheck-mcp"
      ],
      "env": {
        "RETURNCHECK_API_KEY": "your-value",
        "RETURNCHECK_URL": "your-value",
        "RETURNCHECK_FETCH_LOCALLY": "your-value",
        "RETURNCHECK_TIMEOUT_MS": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

ChatGPT connects only to servers on the internet:

Open ChatGPT on the web → Settings → Connectors (Apps)
Press Create or Add (some plans need Developer mode under Advanced first)
Paste the address below, give it a name and save
If it asks you to sign in, sign in with the maker

https://returncheck.m-angelmartinez-fer.workers.dev/mcp

Menu names can differ slightly by plan and over time.

Your choice stays on this device in a cookie; no account needed.

Values you fill in

RETURNCHECK_API_KEY secret env
Optional API key. Without it you get the keyless free trial.
RETURNCHECK_URL env
Service endpoint. Defaults to the hosted service; change it only if you self-host.
RETURNCHECK_FETCH_LOCALLY env
Set to 'false' to let the service fetch the page instead of this machine.
RETURNCHECK_TIMEOUT_MS env
Budget in milliseconds for the local page read. Defaults to 8000.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

We have not read this server’s tool list yet; we check endpoints in rotation.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026

✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account mangelmartinezfer-hue, which owns the repo
… Not checked yet
Still maintained
We have not read this repo from GitHub yet
… Not checked yet
Has a licence
We have not read this repo from GitHub yet
… Not checked yet
Endpoint responds
Not checked yet; we check endpoints in rotation
… Not checked yet
Sign-in with OAuth
Not checked yet; we check endpoints in rotation
… Not checked yet
No hidden instructions in tool descriptions
Not checked yet; we read the tool list when we check the endpoint

Compared with others in Online shops & paymentsi

More stars than 0% of the other 1759 servers in this category
Published to the registry more recently than 33% of the other 1759 servers in this category
Basic checks equal to or better than 100% of the other 1759 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is ReturnCheck safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: RETURNCHECK_API_KEY

Does it run on my computer or in the cloud?

Either way works: install it on your computer or connect to the cloud version.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.1.0) reached the registry 2 months ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Spree Commerce: open-source B2B and marketplace ecommerce, Stripe MCP, MCP Cn Commerce

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Spree Commerce: open-source B2B and marketplace ecommerce

by spree

Open-source B2B and marketplace ecommerce; new stores include an MCP server for AI agents.

Runs in the cloud★ 15,812BSD-3-ClauseUpdated 8 days ago

Install

Stripe MCP

by stripe

Stripe’s official server lets AI view and manage customers, products, payments and invoices. Connect to Stripe’s cloud and sign in with OAuth.

Runs in the cloud★ 2,043MITUpdated 12 months ago

Install

MCP Cn Commerce

by TonyWang-hub

8 read-only MCP platform entries; support is operation-specific; merchant live acceptance pending

Runs on your computer★ 96MITUpdated 28 days ago

Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

ReturnCheck — Return-policy verification for AI shopping agents

ReturnCheck verifies which return policy actually applies to this purchase. For AI shopping agents, it resolves the case with a verified verdict — not a guess.

Give it a product_url and a buyer_country and it returns a verdict (YES / YES_WITH_CONDITIONS / NO / UNKNOWN) with the exact policy clause quoted from the page, the source URL, the return window, and a confidence score. If it cannot verify a clause on the page, it returns UNKNOWN — it never invents.

Built for agent-to-agent commerce: an MCP tool plus x402-friendly micro-pricing at $0.02 per verified answer (UNKNOWN is free; a keyless free trial is available).

Reproducible developer demonstration

Four-verdict evidence demo: synthetic test cases and recorded IKEA US checks

Includes recorded YES, YES_WITH_CONDITIONS, NO and UNKNOWN responses, original test-source links, an IKEA real-merchant field case, and a runnable example. The four-verdict test material is synthetic; only the IKEA case uses real merchant policy text supplied by the caller. This is not an independent benchmark, a live re-test, or a claim of native UCP compatibility.

Why it exists

AI agents are starting to buy things. Before they buy, they need to know if a purchase is reversible — and today no one answers "is this returnable?" in a way a machine can trust and act on. ReturnCheck is the neutral verification primitive for that: it sells to every shopping agent and competes with none of them.

Quick start

MCP (Streamable HTTP) — tool: check_return

https://returncheck.m-angelmartinez-fer.workers.dev/mcp

HTTP

curl -X POST https://returncheck.m-angelmartinez-fer.workers.dev/v1/check \

-H "content-type: application/json" \ -d '{"product_url":"https://store.example/p/shoe","buyer_country":"US","item_condition":"unopened"}'

If you already have the product/policy page rendered, pass it as page_html or page_text — ReturnCheck verifies against it and skips fetching (best coverage, bypasses sites that block server-side reads). It still never invents.

When that content comes from a separate policy page, also send page_source_url with its HTTP(S) URL. This preserves the supplied source in evidence.source_url and the corpus while keeping product_url as the product context. The URL is caller-declared and is not independently fetched. Without it, the existing product_url fallback remains; legacy callers should add the field when supplying a different page. Opened-product alternatives are recovered only for an explicit adjacent generic clause; ambiguous, category-specific or conflicting terms still require the normal verification path.

x402 paid calls

The paid HTTP route is the same endpoint: POST /v1/check.

To inspect the live x402 terms without consuming the free allowance, send a bodyless POST /v1/check with no PAYMENT-SIGNATURE. ReturnCheck responds with the live 402 challenge. Do not send {} or a real check body for this discovery probe.

For a paid call, base64-encode a JSON envelope in the PAYMENT-SIGNATURE header:

"x402Version": 2, "accepted": { "scheme": "exact", "network": "eip155:8453", "amount": "20000", "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913", "payTo": "0xbF428071027402E9b0cE85e22146EDdc028cEB3b", "maxTimeoutSeconds": 60, "extra": { "name": "USD Coin", "version": "2" } }, "payload": { "signature": "0x...", "authorization": { "from": "0x...", "to": "0x...", "value": "20000", "validAfter": "0", "validBefore": "...", "nonce": "0x..." } }, "extensions": { "payment-identifier": { "info": { "required": true, "id": "unique-id-16-to-128-chars" } } } }

Rules:

accepted is the full accepted payment requirement object, not a boolean.
payload directly contains signature and authorization.
The canonical identifier path is extensions["payment-identifier"].info.id.
Do not copy the bazaar discovery extension into PAYMENT-SIGNATURE.
The live 402 challenge is authoritative for current payment terms.
A signed request enters the payment path directly; there is no need to exhaust the free allowance first.
Replay the same paid operation with the same endpoint, body, identifier, signature and nonce. If an authorization expires before the paid call, sign a fresh authorization; that fresh authorization is then the one to replay.
On pending, unconfirmed, HTTP 500, or another ambiguous settlement outcome, do not create a second authorization until the first outcome is reconciled.

What you get back

"verdict": "YES_WITH_CONDITIONS", "returnable": true, "confidence": 0.9, "policy": { "merchant_return_days": 30, "return_category": "FiniteReturnWindow" }, "evidence": { "source_url": "https://store.example/policies/refund-policy", "exact_clause": "Items may be returned within 30 days of delivery for a full refund.", "verified_on": "2026-08-23" } }

Pricing


Verified answer (YES / NO / conditions)	$0.02
UNKNOWN	Free
Keyless free trial	a few calls/day, no signup

Discovery for agents

OpenAPI: /openapi.json
Plugin manifest: /.well-known/ai-plugin.json
Agents manifest: /agents.json
LLM manifest: /llms.txt
MCP tool list: /mcp

Deterministic preflight

Run npm run check to validate registered work and run the full regression suite. Use npm run work:new -- ucp job-name to register new work (payment, corpus and artifact profiles are also available). All registered jobs run automatically on every push and pull request. See AGENTS.md for the permanent review routine. Registered jobs now require a review receipt bound to the exact inputs. The check also detects uncovered changed files and cross-lot corpus contamination. Delivery and historical metrics profiles provide package/snapshot and benchmark checks.

Run npm run validate before reviewing payment packages, UCP evidence or corpus changes. Three offline profiles produce PASS/FAIL, blocking errors, warnings, SHA-256 hashes and fields requiring subsequent AI review. See preflight/README.md for input contracts, limits and commands. npm test includes the preflight regression tests. A PASS is not deployment or payment authorization.

Design principles

Never invent. Every determinate verdict carries a clause verified literally against the page. If it can't be verified, the answer is UNKNOWN.
Frozen contract (v1.0). Fields are only ever added, never broken.
US data first, global architecture. Runs 100% serverless on the edge (Cloudflare Workers + D1 + Workers AI).

Keywords

return policy API · returns verification · AI shopping agents · agentic commerce · MCP server · check_return · x402 · agent-to-agent payments · e-commerce returns · is this returnable · refund policy checker

ReturnCheck

Overview

PopNx MCP’s three pillars

What you can do with it

Install

Before you install

Or run it on your computer

Or run it on your computer

Or run it on your computer

Or run it on your computer

Values you fill in

What it can do

Basic checksi

Maker matches the repo

Still maintained

Has a licence

Endpoint responds

Sign-in with OAuth

No hidden instructions in tool descriptions

Compared with others in Online shops & paymentsi

Common questions

Alternatives

Spree Commerce: open-source B2B and marketplace ecommerce

Stripe MCP

MCP Cn Commerce

README from the maker

ReturnCheck — Return-policy verification for AI shopping agents

Reproducible developer demonstration

Why it exists

Quick start

x402 paid calls

What you get back

Pricing

Discovery for agents

Deterministic preflight

Design principles

Keywords