Roundhouse

FractalAI Verify

The first AI-native Layer 1 blockchain built from scratch in Rust. Post-quantum cryptography (CRYSTALS-Dilithium), Proof of Fractal Work consensus, WASM smart contracts, and 460+ RPC endpoints. Mine FRAC tokens with fractal analysis instead of hash puzzles.

SocialLiveeip155:8453Exactvia cdp
https://fractalai.net.co/api/x402/verify-proof
VerifySignaturePost-quantumPrimitiveMl-dsa-65
Calls · 30d
1
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 9 snapshots so far.
$1.09
Verified settled volume
52 settlements proven x402 by their on-chain EIP-3009 marker.
$0.010
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-09-15 16:14Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xC13789e82661635d9Cea38a53A0390CF9939ef4f

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",
  "price": "$0.01",
  "usage": "POST { message | message_b64, signature, public_key }. First call → 402 with `accepts` (facilitator EIP-3009 gasless, or pay-first txHash). Retry with X-PAYMENT. Verifies an ML-DSA-65 / Dilithium-3 OR Dilithium-2 signature (auto-detected by size) and returns a verdict ($0.01, the floor price).",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2",
        "decimals": 6,
        "assetTransferMethod": "eip3009"
      },
      "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
      "amount": "10000",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 300
    },
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USDC",
        "decimals": 6,
        "settlement": "txHash",
        "instructions": "Facilitator-less: send exactly `amount` USDC to `payTo` on Base, then retry with PAYMENT-SIGNATURE = base64(JSON({ txHash })) (X-PAYMENT also accepted)."
      },
      "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
      "amount": "10000",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 300
    }
  ],
  "service": "FractalAI x402 Pay-per-Verify — verify a post-quantum signature for autonomous agents",
  "resource": {
    "url": "https://fractalai.net.co/api/x402/verify-proof",
    "tags": [
      "verify",
      "signature",
      "post-quantum",
      "primitive",
      "ml-dsa-65"
    ],
    "mimeType": "application/json",
    "description": "Pay-per-Verify: an agent pays $0.01 to verify a post-quantum (ML-DSA-65 / Dilithium-3 or Dilithium-2, NIST FIPS 204; scheme auto-detected by size) signature over a message against a public key. A generic machine-to-machine PQC proof primitive for autonomous agents. x402-native.",
    "serviceName": "FractalAI Verify"
  },
  "extensions": {
    "bazaar": {
      "body": {
        "signature": "BASE64_SIG",
        "public_key": "BASE64_PK",
        "message_b64": "BASE64_BYTES"
      },
      "info": {
        "input": {
          "body": {
            "signature": "BASE64_SIG",
            "public_key": "BASE64_PK",
            "message_b64": "BASE64_BYTES"
          },
          "type": "http",
          "method": "POST",
          "bodyType": "json"
        },
        "output": {
          "type": "json",
          "example": {
            "valid": true,
            "algorithm": "ml-dsa-65",
            "verified_algorithm": "dilithium2"
          }
        }
      },
      "tags": [
        "verify",
        "signature",
        "post-quantum",
        "primitive",
        "ml-dsa-65"
      ],
      "type": "http",
      "method": "POST",
      "output": {
        "type": "json",
        "schema": {
          "type": "object",
          "required": [
            "valid",
            "algorithm",
            "verified_algorithm",
            "input_signature",
            "input_public_key"
          ],
          "properties": {
            "valid": {
              "type": "boolean",
              "description": "True iff the supplied client signature (ML-DSA-65 or Dilithium-2, auto-detected) is valid over the message for the public key."
            },
            "payment": {
              "type": "object",
              "description": "Settlement receipt (scheme, network, asset, txHash, payer, settled)."
            },
            "algorithm": {
              "type": "string",
              "description": "ml-dsa-65 — algorithm of THIS route's attestation signature over the verdict (NOT necessarily the client input scheme; see verified_algorithm)."
            },
            "signature": {
              "type": "string",
              "description": "Base64 ML-DSA-65 / Dilithium-3 (NIST FIPS 204) signature (3309 bytes) by this server over the EXACT bytes echoed in `signed_message` = FRACTALAI-x402-served-v1\\nx402-verify-proof\\n<attestation_digest> (route-separated, 3 lines), attesting the verdict. Verify offline: ml_dsa65.verify(b64(signature), utf8(signed_message), b64(public_key)). Null (with served_signature_error) if the served signer was momentarily unavailable — the paid verdict is still served."
            },
            "public_key": {
              "type": "string",
              "description": "Base64 ML-DSA-65 public key (1952 bytes) that verifies the attestation signature. Null if the served signer was unavailable."
            },
            "message_b64": {
              "type": "string",
              "description": "The exact base64 bytes that were verified (echoed for reproducibility)."
            },
            "signed_message": {
              "type": "string",
              "description": "The EXACT UTF-8 bytes the served signature covers (FRACTALAI-x402-served-v1\\nx402-verify-proof\\n<attestation_digest>). Pass verbatim to ml_dsa65.verify — do not reconstruct it yourself."
            },
            "algorithm_label": {
              "type": "string",
              "description": "ML-DSA-65 / Dilithium-3 (NIST FIPS 204)"
            },
            "input_signature": {
              "type": "string",
              "description": "The exact base64 client signature that was verified (echoed so a third party can recompute attestation_digest from this response alone)."
            },
            "input_public_key": {
              "type": "string",
              "description": "The exact base64 client public key that was verified (echoed for attestation_digest reconstruction)."
            },
            "attestation_digest": {
              "type": "string",
              "description": "sha256 hex over JSON({valid, verified_algorithm, message_b64, message_hash, signature: input_signature, public_key: input_public_key}) — reconstructible from this response."
            },
            "verified_algorithm": {
              "type": "string",
              "description": "The DETECTED scheme of the CLIENT input signature that was verified: ml-dsa-65 or dilithium2."
            },
            "served_signature_error": {
              "type": "string",
              "description": "Present only if the served attestation signer failed; the verdict is still authoritative and paid."
            },
            "verified_algorithm_label": {
              "type": "string",
              "description": "Human label of verified_algorithm, e.g. \"ML-DSA-65 / Dilithium-3 (NIST FIPS 204)\" or \"Dilithium-2 (NIST FIPS 204)\"."
            }
          }
        },
        "example": {
          "valid": true,
          "algorithm": "ml-dsa-65",
          "verified_algorithm": "dilithium2"
        }
      },
      "schema": {
        "type": "object",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "required": [
          "input"
        ],
        "properties": {
          "input": {
            "type": "object",
            "required": [
              "type",
              "method",
              "bodyType",
              "body"
            ],
            "properties": {
              "body": {
                "type": "object"
              },
              "type": {
                "type": "string",
                "const": "http"
              },
              "method": {
                "enum": [
                  "POST",
                  "PUT",
                  "PATCH"
                ],
                "type": "string"
              },
              "headers": {
                "type": "object",
                "additionalProperties": {
                  "type": "string"
                }
              },
              "bodyType": {
                "enum": [
                  "json",
                  "form-data",
                  "text"
                ],
                "type": "string"
              },
              "queryParams": {
                "type": "object",
                "additionalProperties": {
                  "type": "string"
                }
              }
            },
            "additionalProperties": false
          },
          "output": {
            "type": "object",
            "required": [
              "type"
            ],
            "properties": {
              "type": {
                "type": "string"
              },
              "example": {
                "type": "object"
              }
            }
          }
        }
      },
      "bodyType": "json",
      "route_key": "POST /api/x402/verify-proof",
      "description": "Pay-per-Verify: an agent pays $0.01 to verify a post-quantum (ML-DSA-65 / Dilithium-3 or Dilithium-2, NIST FIPS 204; scheme auto-detected by size) signature over a message against a public key. A generic machine-to-machine PQC proof primitive for autonomous agents. x402-native.",
      "serviceName": "FractalAI Verify"
    }
  },
  "x402Version": 2,
  "honest_scope": "Proves ONLY that the signature is a valid Dilithium-2 (NIST FIPS 204) signature over exactly this message for exactly this public key. It says NOTHING about who owns the key, whether it should be trusted, or the truthfulness of the message. Resistant to known classical & quantum attacks per NIST, not \"unbreakable\"."
}

Accepts

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

0.01USDC≈ $0.01 USD
on Base · exact scheme

Pay 0.01 USDC on Base to 0xC137…9ef4f. The signed payment is good for 5 minutes.

Paid to
0xC137…9ef4f
USD Coin contract
0x8335…02913
Payment window
5 minutes
As published
10000 smallest units
0.01USDC≈ $0.01 USD
on Base · exact scheme

Pay 0.01 USDC on Base to 0xC137…9ef4f. The signed payment is good for 5 minutes.

Paid to
0xC137…9ef4f
USD Coin contract
0x8335…02913
Payment window
5 minutes
As published
10000 smallest units
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2",
      "decimals": 6,
      "assetTransferMethod": "eip3009"
    },
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USDC",
      "decimals": 6,
      "settlement": "txHash",
      "instructions": "Facilitator-less: send exactly `amount` USDC to `payTo` on Base, then retry with PAYMENT-SIGNATURE = base64(JSON({ txHash })) (X-PAYMENT also accepted)."
    },
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "body": {
      "signature": "BASE64_SIG",
      "public_key": "BASE64_PK",
      "message_b64": "BASE64_BYTES"
    },
    "info": {
      "input": {
        "body": {
          "signature": "BASE64_SIG",
          "public_key": "BASE64_PK",
          "message_b64": "BASE64_BYTES"
        },
        "type": "http",
        "method": "POST",
        "bodyType": "json"
      },
      "output": {
        "type": "json",
        "example": {
          "valid": true,
          "algorithm": "ml-dsa-65",
          "verified_algorithm": "dilithium2"
        }
      }
    },
    "tags": [
      "verify",
      "signature",
      "post-quantum",
      "primitive",
      "ml-dsa-65"
    ],
    "type": "http",
    "method": "POST",
    "output": {
      "type": "json",
      "schema": {
        "type": "object",
        "required": [
          "valid",
          "algorithm",
          "verified_algorithm",
          "input_signature",
          "input_public_key"
        ],
        "properties": {
          "valid": {
            "type": "boolean",
            "description": "True iff the supplied client signature (ML-DSA-65 or Dilithium-2, auto-detected) is valid over the message for the public key."
          },
          "payment": {
            "type": "object",
            "description": "Settlement receipt (scheme, network, asset, txHash, payer, settled)."
          },
          "algorithm": {
            "type": "string",
            "description": "ml-dsa-65 — algorithm of THIS route's attestation signature over the verdict (NOT necessarily the client input scheme; see verified_algorithm)."
          },
          "signature": {
            "type": "string",
            "description": "Base64 ML-DSA-65 / Dilithium-3 (NIST FIPS 204) signature (3309 bytes) by this server over the EXACT bytes echoed in `signed_message` = FRACTALAI-x402-served-v1\\nx402-verify-proof\\n<attestation_digest> (route-separated, 3 lines), attesting the verdict. Verify offline: ml_dsa65.verify(b64(signature), utf8(signed_message), b64(public_key)). Null (with served_signature_error) if the served signer was momentarily unavailable — the paid verdict is still served."
          },
          "public_key": {
            "type": "string",
            "description": "Base64 ML-DSA-65 public key (1952 bytes) that verifies the attestation signature. Null if the served signer was unavailable."
          },
          "message_b64": {
            "type": "string",
            "description": "The exact base64 bytes that were verified (echoed for reproducibility)."
          },
          "signed_message": {
            "type": "string",
            "description": "The EXACT UTF-8 bytes the served signature covers (FRACTALAI-x402-served-v1\\nx402-verify-proof\\n<attestation_digest>). Pass verbatim to ml_dsa65.verify — do not reconstruct it yourself."
          },
          "algorithm_label": {
            "type": "string",
            "description": "ML-DSA-65 / Dilithium-3 (NIST FIPS 204)"
          },
          "input_signature": {
            "type": "string",
            "description": "The exact base64 client signature that was verified (echoed so a third party can recompute attestation_digest from this response alone)."
          },
          "input_public_key": {
            "type": "string",
            "description": "The exact base64 client public key that was verified (echoed for attestation_digest reconstruction)."
          },
          "attestation_digest": {
            "type": "string",
            "description": "sha256 hex over JSON({valid, verified_algorithm, message_b64, message_hash, signature: input_signature, public_key: input_public_key}) — reconstructible from this response."
          },
          "verified_algorithm": {
            "type": "string",
            "description": "The DETECTED scheme of the CLIENT input signature that was verified: ml-dsa-65 or dilithium2."
          },
          "served_signature_error": {
            "type": "string",
            "description": "Present only if the served attestation signer failed; the verdict is still authoritative and paid."
          },
          "verified_algorithm_label": {
            "type": "string",
            "description": "Human label of verified_algorithm, e.g. \"ML-DSA-65 / Dilithium-3 (NIST FIPS 204)\" or \"Dilithium-2 (NIST FIPS 204)\"."
          }
        }
      },
      "example": {
        "valid": true,
        "algorithm": "ml-dsa-65",
        "verified_algorithm": "dilithium2"
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method",
            "bodyType",
            "body"
          ],
          "properties": {
            "body": {
              "type": "object"
            },
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "POST",
                "PUT",
                "PATCH"
              ],
              "type": "string"
            },
            "headers": {
              "type": "object",
              "additionalProperties": {
                "type": "string"
              }
            },
            "bodyType": {
              "enum": [
                "json",
                "form-data",
                "text"
              ],
              "type": "string"
            },
            "queryParams": {
              "type": "object",
              "additionalProperties": {
                "type": "string"
              }
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object"
            }
          }
        }
      }
    },
    "bodyType": "json",
    "route_key": "POST /api/x402/verify-proof",
    "description": "Pay-per-Verify: an agent pays $0.01 to verify a post-quantum (ML-DSA-65 / Dilithium-3 or Dilithium-2, NIST FIPS 204; scheme auto-detected by size) signature over a message against a public key. A generic machine-to-machine PQC proof primitive for autonomous agents. x402-native.",
    "serviceName": "FractalAI Verify"
  }
}

Provenance

Seen in the source catalog
2026-09-15 16:14Z
Last indexed by Roundhouse
2026-09-24 08:00Z
Last enriched (probe, favicon, geo)
2026-09-15 19:45Z
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. 9 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 FractalAI Verify 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=FractalAI%20Verify'
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://fractalai.net.co/api/x402/verify-proof, 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. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402,
or use an organization key from https://roundhouseai.io/dashboard/team.

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