Roundhouse

flat-rate-llm

Use when an agent must decide whether to write to an address, or clean a list before sending: it scores one email 0-100 with a verdict (ok, risky, disposable, undeliverable, invalid) and the evidence under it: every point lost is itemised with the field that proves it. 12,141 disposable domains from two maintained open lists pinned to a commit, 4,897 free providers, 1,018 role names, typo fix (gmial.com > gmail.com), live MX/SPF/DMARC. No SMTP probe, no API key.

InferenceLiveeip155:8453Exactvia wellknown:flat-rate-llm.kikoribera03.workers.dev
https://flat-rate-llm.kikoribera03.workers.dev/v1/red/email-check
Email validationEmail verificationVerify emailEmail checkerMx recordSpfDmarcDisposable emailRole accountDeliverabilityDnsList cleaning
Calls · 30d
6↑ 5.0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 32 snapshots so far.
$5.38
Verified settled volume
665 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0050
Listed price
As published in the catalog. Always read the live 402 before paying.
—
Calls · 30d
Upstream's own call count for this endpoint, not ours.
—
Unique payers · 30d
Never called
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff

The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider

The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.

Live 402 challenge

Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.

{
  "error": "Payment required",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
      "amount": "5000",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 300
    },
    {
      "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
      "amount": "5000",
      "scheme": "exact",
      "network": "eip155:137",
      "maxTimeoutSeconds": 300
    },
    {
      "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
      "amount": "5000",
      "scheme": "exact",
      "network": "eip155:42161",
      "maxTimeoutSeconds": 300
    }
  ],
  "resource": {
    "url": "https://flat-rate-llm.kikoribera03.workers.dev/v1/red/email-check",
    "tags": [
      "email validation",
      "email verification",
      "verify email",
      "email checker",
      "mx record",
      "spf",
      "dmarc",
      "disposable email",
      "role account",
      "deliverability",
      "dns",
      "list cleaning"
    ],
    "iconUrl": "https://flat-rate-llm.kikoribera03.workers.dev/icon.svg",
    "mimeType": "",
    "description": "Scores one email address 0-100 with a verdict (ok, risky, disposable, undeliverable, invalid) and the evidence under it: every point lost is itemised with the field that proves it. 12,141 disposable domains from two maintained open lists pinned to a commit, 4,897 free providers, 1,018 role names, typo fix (gmial.com > gmail.com), live MX/SPF/DMARC. No SMTP probe, no API key.",
    "serviceName": "Email address check"
  },
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "type": "http",
          "method": "GET",
          "queryParams": {
            "email": "sales@gamil.com"
          }
        },
        "output": {
          "type": "json",
          "example": {
            "mx": [
              {
                "host": "mail.gamil.com",
                "priority": 0
              }
            ],
            "spf": "v=spf1 a mx include:s1394.smtp-spf.sureserver.com -all",
            "typo": {
              "distance": 1,
              "suggestion": "gmail.com"
            },
            "dmarc": null,
            "email": "sales@gamil.com",
            "hasMx": true,
            "local": "sales",
            "score": 15,
            "domain": "gamil.com",
            "nullMx": false,
            "reasons": [
              "looks like a typo of gmail.com",
              "\"sales\" is a role mailbox reserved by RFC 2142",
              "no DMARC record"
            ],
            "scoring": [
              {
                "check": "typo",
                "field": "typo",
                "points": -50
              },
              {
                "check": "role mailbox",
                "field": "roleMatch",
                "points": -30
              },
              {
                "check": "DMARC",
                "field": "dmarc",
                "points": -5
              }
            ],
            "verdict": "risky",
            "passMark": 80,
            "roleMatch": {
              "name": "sales",
              "source": "RFC 2142",
              "category": "rfc2142"
            },
            "didYouMean": "sales@gmail.com",
            "disposable": false,
            "dmarcPolicy": null,
            "roleAccount": true,
            "syntaxValid": true,
            "freeProvider": false,
            "domainResolves": true,
            "disposableMatch": null
          }
        }
      },
      "schema": {
        "type": "object",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "required": [
          "input"
        ],
        "properties": {
          "input": {
            "type": "object",
            "required": [
              "type",
              "method"
            ],
            "properties": {
              "type": {
                "type": "string",
                "const": "http"
              },
              "method": {
                "enum": [
                  "GET"
                ],
                "type": "string"
              },
              "queryParams": {
                "type": "object",
                "required": [
                  "email"
                ],
                "properties": {
                  "email": {
                    "type": "string",
                    "description": "The address to check, e.g. someone@example.com."
                  }
                }
              }
            },
            "additionalProperties": false
          },
          "output": {
            "type": "object",
            "required": [
              "type"
            ],
            "properties": {
              "type": {
                "type": "string"
              },
              "example": {
                "type": "object"
              }
            }
          }
        }
      }
    }
  },
  "x402Version": 2
}

Accepts

The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.

0.005USDC≈ $0.005 USD
on Base · exact scheme

Pay 0.005 USDC on Base to 0xc210…7e9Ff. The signed payment is good for 5 minutes.

Paid to
0xc210…7e9Ff
USD Coin contract
0x8335…02913
Payment window
5 minutes
As published
5000 smallest units
5000units
on Polygon · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
0xc210…7e9Ff
Token contract
0x3c49…c3359
Payment window
5 minutes
5000units
on Arbitrum · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
0xc210…7e9Ff
Token contract
0xaf88…e5831
Payment window
5 minutes
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
    "amount": "5000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
    "amount": "5000",
    "scheme": "exact",
    "network": "eip155:137",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
    "amount": "5000",
    "scheme": "exact",
    "network": "eip155:42161",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "email": "sales@gamil.com"
        },
        "type": "http",
        "method": "POST",
        "bodyType": "json",
        "discoverable": true
      },
      "output": {
        "type": "json",
        "example": {
          "mx": [
            {
              "host": "mail.gamil.com",
              "priority": 0
            }
          ],
          "spf": "v=spf1 a mx include:s1394.smtp-spf.sureserver.com -all",
          "typo": {
            "distance": 1,
            "suggestion": "gmail.com"
          },
          "dmarc": null,
          "email": "sales@gamil.com",
          "hasMx": true,
          "local": "sales",
          "score": 15,
          "domain": "gamil.com",
          "nullMx": false,
          "reasons": [
            "looks like a typo of gmail.com",
            "\"sales\" is a role mailbox reserved by RFC 2142",
            "no DMARC record"
          ],
          "scoring": [
            {
              "check": "typo",
              "field": "typo",
              "points": -50
            },
            {
              "check": "role mailbox",
              "field": "roleMatch",
              "points": -30
            },
            {
              "check": "DMARC",
              "field": "dmarc",
              "points": -5
            }
          ],
          "verdict": "risky",
          "passMark": 80,
          "roleMatch": {
            "name": "sales",
            "source": "RFC 2142",
            "category": "rfc2142"
          },
          "didYouMean": "sales@gmail.com",
          "disposable": false,
          "dmarcPolicy": null,
          "roleAccount": true,
          "syntaxValid": true,
          "freeProvider": false,
          "domainResolves": true,
          "disposableMatch": null
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
—
Last indexed by Roundhouse
2026-11-07 01:15Z
Last enriched (probe, favicon, geo)
2026-10-17 21:15Z
x402 version
2
Max timeout
300s
Liveness probe
HTTP 402
Report

Hand this page to an agent

Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.

GET api.roundhouseai.io/v0/endpoints

This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 32 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.

Open skill.md
Show the prompt
Using Roundhouse, look up the x402 service flat-rate-llm and tell me whether it is
worth paying: what a call costs, whether the endpoint answered when last probed, and what
its payment record actually shows.

curl -s 'https://api.roundhouseai.io/v0/endpoints?q=flat-rate-llm'
curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>'

Then call it: read the price from the live 402 at https://flat-rate-llm.kikoribera03.workers.dev/v1/red/email-check, never from
a cached figure, and pay with an x402 client.

The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except
/v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at
GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at
https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further.

If you do not have Roundhouse tools or skills installed, read
https://roundhouseai.io/skill.md first — it is the whole procedure.