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protocol_matrix

Protocol matrix

Which agentic commerce protocols (UCP, ACP, PAP, WebMCP, MCP, payments) stores actually support, stage by stage, with evidence labels.

NO LOGINREAD-ONLYNOT DESTRUCTIVEIDEMPOTENTNOT REACHES THE OPEN WEB

What it does

Read ARC's neutral Protocol Matrix: for UCP, ACP, PAP, WebMCP, MCP and agent payment protocols, how many checked stores declare, validate, answer and transact, with evidence labels (Measured / Inferred / Not measured). Saved checks only; no store requests or model calls. CC-BY-4.0.

Limits: Free saved-data read, cached 5 minutes.

Arguments

NameTypeRequiredDescription
protocol"ucp" | "acp" | "pap" | "webmcp" | "mcp" | "payments"noOptional: one protocol id.
Full input JSON Schema
INPUT SCHEMA
{
  "type": "object",
  "properties": {
    "protocol": {
      "type": "string",
      "enum": [
        "ucp",
        "acp",
        "pap",
        "webmcp",
        "mcp",
        "payments"
      ],
      "description": "Optional: one protocol id."
    }
  },
  "additionalProperties": false
}

Call it

From Claude, Cursor, ChatGPT or VS Code, connect the server (config) and ask in plain words; the client picks the tool. Or call it directly with JSON-RPC:

CURL · JSON-RPC
curl -s https://www.arcreport.ai/api/ask \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"protocol_matrix","arguments":{"protocol":"ucp"}}}'
JAVASCRIPT
const res = await fetch("https://www.arcreport.ai/api/ask", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "protocol_matrix",
      "arguments": {
        "protocol": "ucp"
      }
    }
  }),
});
const { result } = await res.json();
const data = JSON.parse(result.content[0].text); // result.isError is true on errors
console.log(data);
PYTHON
import json, requests

res = requests.post("https://www.arcreport.ai/api/ask", json={
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
        "name": "protocol_matrix",
        "arguments": {
            "protocol": "ucp"
        }
    }
}, timeout=30)
result = res.json()["result"]
print(json.loads(result["content"][0]["text"]))

REST equivalent

GET /api/protocols. Returns every protocol; the MCP tool can filter to one. Documented in openapi.json.

CURL · GET
curl -s 'https://www.arcreport.ai/api/protocols'