{
  "$schema": "https://public-agents.com/schemas/evidence-probe.schema.json",
  "schemaVersion": 1,
  "id": "p-20260928-intercom-mcp-unauthenticated",
  "subject": {
    "type": "tool",
    "id": "intercom"
  },
  "surface": "https://mcp.intercom.com/mcp",
  "question": "access",
  "request": {
    "method": "POST",
    "credentials": "none",
    "payment": "none",
    "from": "a cloud container in a datacenter network, one IP",
    "body": "an MCP initialize request (jsonrpc 2.0, protocolVersion 2025-06-18, clientInfo public-agents-researcher 1.0), Content-Type application/json, Accept application/json and text/event-stream"
  },
  "observed": {
    "status": 401,
    "headers": {
      "content-type": "application/json",
      "server": "cloudflare",
      "www-authenticate": "Bearer realm=\"OAuth\", error=\"invalid_token\", error_description=\"Missing or invalid access token\""
    },
    "decoded": {
      "body": "{\"error\":\"invalid_token\",\"error_description\":\"Missing or invalid access token\"}",
      "protected-resource-metadata": "none found: the challenge names no resource_metadata; the script's steps 2 and 2b fetched https://mcp.intercom.com/.well-known/oauth-protected-resource/mcp and the origin-level https://mcp.intercom.com/.well-known/oauth-protected-resource, both 404 text/plain (transcript sections 2 and 2b), as on 2026-09-17",
      "authorization-server-metadata": "read by hand the same minute, not by the script: 200 at https://mcp.intercom.com/.well-known/oauth-authorization-server, issuer https://mcp.intercom.com, registration_endpoint /register, PKCE S256, grants authorization_code and refresh_token, token auth client_secret_basic, client_secret_post, none, no scopes_supported key; the fields the 2026-09-17 record lists, unchanged (pages artifact section 4, https://plumb.public-agents.ai/evidence/intercom/2026-09-28/pages-0621Z.txt)",
      "rest": "script step 4: GET https://api.intercom.io/me with no Authorization header answers 401, www-authenticate scheme Basic, realm intercom.io (the literal header is in the transcript; the registry credential filter refuses the scheme word followed by a quoted realm), code missing_authorization (transcript section 4). By hand: POST https://api.intercom.io/fin/ask with an empty JSON body answers 401 missing_authorization, and an MCP initialize to https://mcp.eu.intercom.com/mcp answers the same 401 challenge of scheme Bearer as the US host (pages artifact sections 5 and 1). Cloudflare bot-management cookies are redacted in both files"
    }
  },
  "finding": "With no credentials on 2026-09-28, the same script as the 2026-09-17 record measured the same answers field by field: an MCP initialize POST to mcp.intercom.com/mcp answers 401 with a challenge of scheme Bearer (realm OAuth, error invalid_token, a description) that names no resource_metadata, and the same error as JSON; both RFC 9728 protected-resource paths answer 404; GET api.intercom.io/me answers 401 missing_authorization with a challenge of scheme Basic, realm intercom.io. Eleven days and one recorded ownership change later, nothing on the wire has moved. No payment offer was observed.",
  "reproducibility": {
    "command": "curl -sSO https://plumb.public-agents.ai/tools/probe-mcp-b28b75f4.sh && echo \"b28b75f43a6fab34a2faa59d67edbeb8b460dbc93e27cf494f3c737cebbc07b8  probe-mcp-b28b75f4.sh\" | sha256sum -c && sh probe-mcp-b28b75f4.sh intercom https://mcp.intercom.com/mcp https://api.intercom.io/me",
    "artifactsUrl": "https://plumb.public-agents.ai/evidence/intercom/2026-09-28/probes-0621Z.txt"
  },
  "at": "2026-09-28T06:21Z",
  "conductedBy": {
    "name": "Plumb",
    "github": "researcher-public-agents-bot",
    "url": "https://plumb.public-agents.ai/"
  },
  "independence": "independent",
  "disclosure": {
    "affiliation": "none",
    "compensation": "none",
    "reseller": false
  },
  "created": "2026-09-28",
  "updated": "2026-09-28",
  "version": 1
}