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Attester — Verification Oracle & Verified Research

Independent verification of agent work products — citation-support checks and data/schema validation returning wallet-signed attestations (EIP-191) — plus cited coding research that ships pre-verified with a signed attestation over its citations. USDC on Base mainnet via CDP facilitator. Free per-wallet quotas, free receipt verification, machine-readable policy, llms.txt + OpenAPI.

Pay from $0.005 to $0.25 per request in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.

UPTIME 24H 100% │ 7D 100% │ 30D 100%

BASE URL https://attester.dev │ WEBSITE https://attester.dev │ ENDPOINTS 5 │ NETWORK Base │ ASSET USDC │ MEMBER SINCE 2026-07-21 │ MONITORED SINCE 2026-07-21

ASSESSMENT

updated 1h ago

Evidence-backed signals, not a single score. Click any chip for the proof. Measured values stay read-only; unknown is honest.

reliability 100%

uptime 24h: 100%
uptime 7d: 100%
uptime 30d: 100%
uptime 90d: 100%
response p95: 342ms
avg response: 188ms
total checks: 24

compliance A (11/11)

11 of 11 x402 conformance checks pass. Full checklist below.

jump to compliance checklist

price $0.005 to $0.25 (p38 in AI)

price (min): $0.005
price (max): $0.25
category percentile (min): p38 in AI
category percentile (max): p66 in AI
endpoints / prices: 5 / 4
model: tiered
stability: 100%

risk clean

No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.

traction $0.14 30d · 1 buyers

volume 30d: $0.14
buyers 30d: 1
settlements 30d: 6
last settlement: 2026-07-21
top buyer share: 100% of 30d volume
trend 7d vs 30d: 4.29x the 30d daily rate
networks: eip155:8453

Conservative undercount: only USDC settlements via facilitators we measure are counted. A measured floor, not an estimate.

Top buyer share is a concentration signal, not part of the ranking score.

WHAT IT DOES

ai-derived

Attester provides verification and research services through an API, allowing users to verify work, conduct code research, check spending, and receive judge reports.

category: verification-oracle
in: body
auth: api key

verificationcode-researchspend-checkingjudgingreporting

AI-generated summary. The measured data is never altered by it.

ENDPOINTS

Service endpoints with HTTP method, path, description, pricing, and network
METHOD	PATH	PRICE	NETWORK	ASSET
POST	/code-research	$0.10	Base	USDC
GET	/judge	$0.10	Base	USDC
GET	/spend-check	$0.005	Base	USDC
POST	/verify	$0.25	Base	USDC
GET	/watchtower/report	$0.05	Base	USDC

5 endpoints

REQUEST / RESPONSE EXAMPLE

An unpaid request to GET /judge returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.

// request

curl -i 'https://attester.dev/judge'

// 402 response (captured by monitor) · 5 payloads · click to expand

[
  {
    "error": "Payment required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "payTo": "0x57407D691F755cAa107647718F3582a8A87467dD",
        "amount": "250000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 300
      }
    ],
    "resource": {
      "url": "https://attester.dev/verify",
      "tags": [
        "verification",
        "attestation",
        "agents",
        "trust",
        "audit"
      ],
      "mimeType": "application/json",
      "description": "Verification Oracle: independent checks on another agent's work (citation support, data/schema validation) returning a wallet-signed attestation. $0.25 USDC per verification.",
      "serviceName": "Verification Oracle"
    },
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "job": {
                "type": "citation",
                "claim": "Python was created by Guido van Rossum",
                "sources": [
                  "https://en.wikipedia.org/wiki/Python_(programming_language)"
                ]
              }
            },
            "type": "http",
            "method": "POST",
            "bodyType": "json"
          },
          "output": {
            "type": "json",
            "example": {
              "verdict": "pass",
              "signature": "0x…",
              "confidence": 0.83,
              "attestation": {
                "service_version": "0.2.0",
                "verifier_address": "0x31520f9c14360470040807fAba64938ebcfF9C8f"
              }
            }
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "required": [
            "input"
          ],
          "properties": {
            "input": {
              "type": "object",
              "required": [
                "type",
                "method",
                "bodyType",
                "body"
              ],
              "properties": {
                "body": {
                  "type": "object",
                  "required": [
                    "job"
                  ],
                  "properties": {
                    "job": {
                      "type": "object",
                      "required": [
                        "type"
                      ],
                      "properties": {
                        "type": {
                          "enum": [
                            "citation",
                            "code",
                            "data"
                          ],
                          "type": "string"
                        },
                        "claim": {
                          "type": "string"
                        },
                        "sources": {
                          "type": "array",
                          "items": {
                            "type": "string"
                          }
                        }
                      },
                      "description": "Verification job: citation support check, data/schema validation"
                    }
                  }
                },
                "type": {
                  "type": "string",
                  "const": "http"
                },
                "method": {
                  "enum": [
                    "POST"
                  ],
                  "type": "string"
                },
                "bodyType": {
                  "enum": [
                    "json"
                  ],
                  "type": "string"
                }
              },
              "additionalProperties": false
            },
            "output": {
              "type": "object",
              "required": [
                "example"
              ],
              "properties": {
                "example": {
                  "type": "object"
                }
              }
            }
          }
        },
        "category": "ai",
        "discoverable": true
      }
    },
    "x402Version": 2
  },
  {
    "error": "Payment required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "payTo": "0x57407D691F755cAa107647718F3582a8A87467dD",
        "amount": "100000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 300
      }
    ],
    "resource": {
      "url": "https://attester.dev/code-research",
      "tags": [
        "research",
        "coding",
        "citations",
        "docs",
        "agents"
      ],
      "mimeType": "application/json",
      "description": "Cited coding research for agents: library/API usage answers, error diagnosis and best-practice lookups with real citations. $0.10 USDC per call.",
      "serviceName": "Cited Coding Research"
    },
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "query": "How do I stream responses with the OpenAI Python SDK?",
              "context": null
            },
            "type": "http",
            "method": "POST",
            "bodyType": "json"
          },
          "output": {
            "type": "json",
            "example": {
              "answer": "Use stream=True ...",
              "citations": [
                {
                  "url": "https://platform.openai.com/docs",
                  "title": "OpenAI docs",
                  "snippet": "..."
                }
              ]
            }
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "required": [
            "input"
          ],
          "properties": {
            "input": {
              "type": "object",
              "required": [
                "type",
                "method",
                "bodyType",
                "body"
              ],
              "properties": {
                "body": {
                  "type": "object",
                  "required": [
                    "query"
                  ],
                  "properties": {
                    "query": {
                      "type": "string",
                      "description": "Coding question to research"
                    },
                    "context": {
                      "type": [
                        "string",
                        "null"
                      ],
                      "description": "Optional extra context"
                    }
                  }
                },
                "type": {
                  "type": "string",
                  "const": "http"
                },
                "method": {
                  "enum": [
                    "POST"
                  ],
                  "type": "string"
                },
                "bodyType": {
                  "enum": [
                    "json"
                  ],
                  "type": "string"
                }
              },
              "additionalProperties": false
            },
            "output": {
              "type": "object",
              "required": [
                "example"
              ],
              "properties": {
                "example": {
                  "type": "object"
                }
              }
            }
          }
        },
        "category": "ai",
        "discoverable": true
      }
    },
    "x402Version": 2
  },
  {
    "error": "Payment required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "payTo": "0x57407D691F755cAa107647718F3582a8A87467dD",
        "amount": "100000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 300
      }
    ],
    "resource": {
      "url": "https://attester.dev/judge",
      "mimeType": "application/json",
      "description": "QA Judge (use POST; full Bazaar metadata on POST)."
    },
    "x402Version": 2
  },
  {
    "error": "Payment required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "payTo": "0x57407D691F755cAa107647718F3582a8A87467dD",
        "amount": "50000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 300
      }
    ],
    "resource": {
      "url": "https://attester.dev/watchtower/report",
      "mimeType": "application/json",
      "description": "SLA Watchtower report (use POST; full Bazaar metadata on POST)."
    },
    "x402Version": 2
  },
  {
    "error": "Payment required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "payTo": "0x57407D691F755cAa107647718F3582a8A87467dD",
        "amount": "5000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 300
      }
    ],
    "resource": {
      "url": "https://attester.dev/spend-check",
      "mimeType": "application/json",
      "description": "Spend Check (use POST; full Bazaar metadata on POST)."
    },
    "x402Version": 2
  }
]

UPTIME

RESPONSE TIME

90d UPTIME 100%

UPTIME 90D 100%

AVG RESP 185ms

TOTAL CHECKS 28

RECENT CHECKS

TIME STATUS RESP

20:56:04 UTC ● OK 116ms

20:40:04 UTC ● OK 96ms

20:24:05 UTC ● OK 271ms

20:08:04 UTC ● OK 184ms

19:52:05 UTC ● OK 166ms

19:36:04 UTC ● OK 78ms

19:20:04 UTC ● OK 165ms

19:04:05 UTC ● OK 105ms

18:48:04 UTC ● OK 126ms

18:32:05 UTC ● OK 123ms

18:16:05 UTC ● OK 95ms

18:00:04 UTC ● OK 149ms

17:44:04 UTC ● OK 148ms

17:28:05 UTC ● OK 132ms

17:12:04 UTC ● OK 155ms

16:56:04 UTC ● OK 152ms

16:40:05 UTC ● SLOW 311ms

16:24:04 UTC ● OK 76ms

OVER TIME

All charts share the 90d window selected here. Every series is also served as JSON at /api/v1/services/attester-verification-oracle-verified-research/price, /scores, /volume and /buyers. On-chain volume and distinct buyers are measured over the service's settlement address and are a conservative undercount (only settlements that reach a measured facilitator are counted). The on-chain series roll up hourly, so the latest day can be up to about an hour behind; distinct buyers are counted per payout address, so a service that settles to more than one address is an upper bound.

PRICE (captured 402, USD)

Median across 5 endpoints. Use the selector to isolate one.

SUB-SCORES (uptime + x402 compliance)

VOLUME (on-chain settlement, USD)

DISTINCT BUYERS

COMPLIANCE

11/11 checks pass · grade A

402 payload captured
accepts[] array present
payTo address recoverable
payTo at accepts[0].payTo (conformant shape)
payTo is a valid on-chain address
atomic price declared
atomic price in a sane range
asset (token) address declared
network resolves to CAIP-2
payment scheme declared
served over HTTPS

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status

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RUN THIS SERVICE?

Keep this listing accurate: propose changes to the name, description, website, category or add new endpoints to monitor. Ownership is verified with a domain proof and every change is reviewed manually; measured data stays read-only.

[ update this listing ]