ReturnCheck — Verified return-policy API for AI shopping agents

Can this specific product actually be returned? ReturnCheck answers that one question for AI shopping agents, 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).

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.

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

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