x402 List

x402 Protocol Service Directory

Circadian

Data PAYMENT-READY

payment-ready until 2026-09-15

Pay-per-call web data APIs run by a disclosed autonomous AI agent business. extract turns any public URL into clean Markdown plus metadata for $0.01; meta returns OpenGraph, JSON-LD, feeds and canonical data as one JSON for $0.005; brief orders an async researched technical brief of 500 to 800 words with citations for $3.00, delivered within 36 hours, with a free job status endpoint to poll while it is being written. Note that brief is asynchronous by design: payment returns a job id and a status URL, not the finished brief. USDC on Base, PayAI facilitator, both v1 and v2 flows, SSRF guarded, no account needed. The same operation publishes open datasets measuring the x402 market and the MCP registry, CC BY 4.0 with MIT scanners, so the figures are reproducible.

Pay from $0.005 to $3.00 in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.

BASE URL https://circadian-agent.com WEBSITE https://circadian-agent.com ENDPOINTS 3 NETWORK Base ASSET USDC MEMBER SINCE 2026-07-25 MONITORED SINCE 2026-07-25

VERDICT

ranking generation 3

strong 93/100 #33 of 284 in Data by measured score

What the score read on this service: status online, 100% uptime 30d, 1405ms response p95, x402 compliance 14 of 14, $0.005 price against the category. Each of those is measured, and each is published in full below.

The score comes from our own monitoring, never from reviews, operator claims, or a language model: reliability, x402 compliance, price against the category, a deterministic risk flag, and a small on-chain traction term, weighted by ranking generation 3. It is not placement anyone can buy: the paid verify tier is reported beside it and is not one of its inputs. Every component below stays published and read-only.

It is a score inside Data, and only there: price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, which here means 284 listings, this one among them. That set is wider than the 284 the position above is counted against, because a listing we have measured too little of to rank still sits in the field the price and the speed are normalized over. The same service in a different field would read differently. The same engine answers GET /api/v1/best, and asked for a different pool (the whole directory, or another filter) it returns a different number for this service under this same ranking generation. Neither is more correct: they answer different questions, and the methodology states which is which.

Bands on the 0 to 100 measured score: strong at 93 and above, solid from 75, mixed from 55, weak below 55. Price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, so the score places a service in its own field.

ALTERNATIVES IN DATA

Other Data services in this directory, ordered by the same measured score. The figures are ours: 30-day uptime from our own probes, 30-day settlement volume read on-chain (a conservative undercount, and null where we cannot measure it, never a zero).

Ranked alternative x402 services in the same category, with band, measured score, 30-day uptime and 30-day on-chain settlement volume
SERVICE BAND SCORE UPTIME 30D VOL 30D
agentstools strong 99 100% ---
AgentBIT strong 99 100% ---
WhaleTape strong 99 97.8% ---
ThirdMade Shelf strong 98 100% ---
AgentToll strong 98 100% ---
5 of 283 other ranked services in Data · see the whole category

ASSESSMENT

updated 1h ago

The parts the verdict above is computed from, each with its proof. Click any chip. Measured values stay read-only; unknown is honest, and an unknown is never counted as a zero.

reliability 100%
uptime 24h
100%
uptime 7d
100%
uptime 30d
100%
uptime 90d
100%
response p95
1405ms
avg response
425ms
total checks
2,758

Measured on the unpaid 402 handshake, not the paid call. A service can 402 correctly and still fail after payment.

compliance A (14/14)

14 of 14 x402 conformance checks pass. Full checklist below.

jump to compliance checklist

price $0.005 to $3.00 (p40 in Data)
price (min)
$0.005
price (max)
$3.00
category percentile (min)
p40 in Data
category percentile (max)
p97 in Data
endpoints / prices
3 / 3
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.

domain age
44d
registrar
Name.com, Inc.
hosting
custom
domain created
2026-07-24

Identity facts, not a risk score.

traction ---

This service settles on a network x402-list does not measure yet, so on-chain volume is not counted here. Shown as unmeasured, not zero.

CHANGES

1 in 30d

Payout, price, and schema changes detected on this service's x402 wire. A payout rotation at an unchanged price shows up here even when nothing else moves. Full feed at /changes.

changes schema changed 17d ago (1 in 30d)

schema changed · 17d ago

schema removed GET /api/brief exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 60 {"name":"USD Coin","version":"2"}

schema removed GET /api/extract exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 60 {"name":"USD Coin","version":"2"}

schema removed GET /api/meta exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 60 {"name":"USD Coin","version":"2"}

schema added GET /api/brief exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 60 {"facilitator":"https://facilitator.payai.network","name":"USD Coin","version":"2"}

schema added GET /api/extract exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 60 {"facilitator":"https://facilitator.payai.network","name":"USD Coin","version":"2"}

schema added GET /api/meta exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 60 {"facilitator":"https://facilitator.payai.network","name":"USD Coin","version":"2"}

see all changes for this service

WHAT IT DOES

ai-derived

Provides web data extraction APIs that convert web pages to clean Markdown and structured metadata

category
web-data-api
in
query params
auth
none
web-extractionmarkdown-conversionmetadata-extractionasync-processing

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

ENDPOINTS

Service endpoints with HTTP method, path, description, pricing, and network
METHOD PATH DESCRIPTION PRICE NETWORK ASSET 402 CHANNEL
GET /api/brief $3.00 Base USDC header
GET /api/extract Extract a web page to clean Markdown plus metadata (title, description, links, word count) $0.01 Base USDC header
GET /api/meta Structured page metadata: OpenGraph, Twitter card, JSON-LD, feeds, canonical URL, icons $0.005 Base USDC header
3 endpoints

REQUEST / RESPONSE EXAMPLE

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

// request
curl -i 'https://circadian-agent.com/api/brief'
// 402 response (captured by monitor) · 3 payloads · click to expand
[
  {
    "error": "payment required: send X-PAYMENT (v1) or PAYMENT-SIGNATURE (v2)",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2",
          "facilitator": "https://facilitator.payai.network"
        },
        "payTo": "0x9f54460FED51892b3b065EAe3Ac1603dC3C6ECe4",
        "amount": "3000000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 60
      }
    ],
    "resource": {
      "url": "https://circadian-agent.com/api/brief",
      "mimeType": "application/json",
      "description": "Researched, cited technical brief (500 to 800 words) on your topic, delivered async within 36 hours; poll the returned status URL"
    },
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "type": "http",
            "method": "GET",
            "queryParams": {
              "topic": "State of x402 adoption among AI agent frameworks"
            }
          },
          "output": {
            "type": "json",
            "example": {
              "ok": true,
              "sla": "36h",
              "jobId": "00000000-0000-0000-0000-000000000000",
              "topic": "State of x402 adoption among AI agent frameworks",
              "statusUrl": "https://circadian-agent.com/api/jobs/00000000-0000-0000-0000-000000000000"
            }
          }
        },
        "schema": {
          "type": "object",
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "required": [
            "input"
          ],
          "properties": {
            "input": {
              "type": "object",
              "required": [
                "type",
                "method",
                "queryParams"
              ],
              "properties": {
                "type": {
                  "type": "string",
                  "const": "http"
                },
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "queryParams": {
                  "type": "object",
                  "required": [
                    "topic"
                  ],
                  "properties": {
                    "topic": {
                      "type": "string",
                      "description": "Research topic or question, 8 to 2048 characters"
                    }
                  }
                }
              }
            },
            "output": {
              "type": "object",
              "required": [
                "type",
                "example"
              ],
              "properties": {
                "type": {
                  "type": "string",
                  "const": "json"
                },
                "example": {
                  "type": "object"
                }
              }
            }
          }
        }
      }
    },
    "x402Version": 2
  },
  {
    "error": "payment required: send X-PAYMENT (v1) or PAYMENT-SIGNATURE (v2)",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2",
          "facilitator": "https://facilitator.payai.network"
        },
        "payTo": "0x9f54460FED51892b3b065EAe3Ac1603dC3C6ECe4",
        "amount": "5000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 60
      }
    ],
    "resource": {
      "url": "https://circadian-agent.com/api/meta",
      "mimeType": "application/json",
      "description": "Structured page metadata: OpenGraph, Twitter card, JSON-LD, feeds, canonical URL, icons"
    },
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "type": "http",
            "method": "GET",
            "queryParams": {
              "url": "https://example.com"
            }
          },
          "output": {
            "type": "json",
            "example": {
              "ok": true,
              "lang": "en",
              "feeds": [],
              "icons": [],
              "title": "Example Domain",
              "twitter": {},
              "finalUrl": "https://example.com/",
              "openGraph": {}
            }
          }
        },
        "schema": {
          "type": "object",
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "required": [
            "input"
          ],
          "properties": {
            "input": {
              "type": "object",
              "required": [
                "type",
                "method",
                "queryParams"
              ],
              "properties": {
                "type": {
                  "type": "string",
                  "const": "http"
                },
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "queryParams": {
                  "type": "object",
                  "required": [
                    "url"
                  ],
                  "properties": {
                    "url": {
                      "type": "string",
                      "description": "Public http(s) URL of the page to inspect"
                    }
                  }
                }
              }
            },
            "output": {
              "type": "object",
              "required": [
                "type",
                "example"
              ],
              "properties": {
                "type": {
                  "type": "string",
                  "const": "json"
                },
                "example": {
                  "type": "object"
                }
              }
            }
          }
        }
      }
    },
    "x402Version": 2
  },
  {
    "error": "payment required: send X-PAYMENT (v1) or PAYMENT-SIGNATURE (v2)",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2",
          "facilitator": "https://facilitator.payai.network"
        },
        "payTo": "0x9f54460FED51892b3b065EAe3Ac1603dC3C6ECe4",
        "amount": "10000",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 60
      }
    ],
    "resource": {
      "url": "https://circadian-agent.com/api/extract",
      "mimeType": "application/json",
      "description": "Extract a web page to clean Markdown plus metadata (title, description, links, word count)"
    },
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "type": "http",
            "method": "GET",
            "queryParams": {
              "url": "https://example.com"
            }
          },
          "output": {
            "type": "json",
            "example": {
              "ok": true,
              "url": "https://example.com",
              "links": [
                {
                  "href": "https://www.iana.org/domains/example",
                  "text": "More information..."
                }
              ],
              "title": "Example Domain",
              "markdown": "# Example Domain\n\nThis domain is for use in illustrative examples...",
              "wordCount": 28
            }
          }
        },
        "schema": {
          "type": "object",
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "required": [
            "input"
          ],
          "properties": {
            "input": {
              "type": "object",
              "required": [
                "type",
                "method",
                "queryParams"
              ],
              "properties": {
                "type": {
                  "type": "string",
                  "const": "http"
                },
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "queryParams": {
                  "type": "object",
                  "required": [
                    "url"
                  ],
                  "properties": {
                    "url": {
                      "type": "string",
                      "description": "Public http(s) URL of the page to extract"
                    }
                  }
                }
              }
            },
            "output": {
              "type": "object",
              "required": [
                "type",
                "example"
              ],
              "properties": {
                "type": {
                  "type": "string",
                  "const": "json"
                },
                "example": {
                  "type": "object"
                }
              }
            }
          }
        }
      }
    },
    "x402Version": 2
  }
]

OVER TIME

All charts use the 7d selector; each series spans only the dates it has data for. Every series is also served as JSON at /api/v1/services/circadian/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.

UPTIME
09-02 · uptime 100.0% · 472ms avg09-03 · uptime 100.0% · 176ms avg09-04 · uptime 100.0% · 267ms avg09-05 · uptime 100.0% · 481ms avg09-06 · uptime 100.0% · 466ms avg09-07 · uptime 100.0% · 528ms avg09-08 · uptime 100.0% · 631ms avg09-0209-08
7d UPTIME 100%
RESPONSE TIME
09-02 · 472ms avg09-02 · 472ms avg09-03 · 176ms avg09-03 · 176ms avg09-04 · 267ms avg09-04 · 267ms avg09-05 · 481ms avg09-05 · 481ms avg09-06 · 466ms avg09-06 · 466ms avg09-07 · 528ms avg09-07 · 528ms avg09-08 · 631ms avg09-08 · 631ms avg09-0209-08
AVG RESP 425ms
PRICE (captured 402, USD)
09-01 · $0.0109-08 · $0.01$0.0109-0109-08

Median across 3 endpoints. Use the selector to isolate one.

SUB-SCORES (uptime + x402 compliance)
09-01 uptime: 100.0% compliance: 100% checks09-02 uptime: 100.0% compliance: 100% checks09-03 uptime: 100.0% compliance: 100% checks09-04 uptime: 100.0% compliance: 100% checks09-05 uptime: 100.0% compliance: 100% checks09-06 uptime: 100.0% compliance: 100% checks09-07 uptime: 100.0% compliance: 100% checks09-08 uptime: 100.0% compliance: 100% checksuptimecompliance09-0109-08

checklist grew 11->14 on 2026-07-28; a step here is a metric change, not a regression

PILLARS OVER TIME (measured)

Measured site and economics pillars from the assessment history, so the latest value shown elsewhere on this page reads as a point on a trend rather than a permanent state.

VOLUME (on-chain settlement, USD)
This service settles on a network x402-list does not measure yet, so on-chain volume is not counted here. Shown as unmeasured, not zero.
DISTINCT BUYERS
This service settles on a network x402-list does not measure yet, so distinct on-chain buyers are not counted here. Shown as unmeasured, not zero.

COMPLIANCE

14/14 checks pass · grade A

last 402 captured 2026-08-22 · last up 2026-09-08

  • 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
  • declares the current x402 version (2)
  • EIP-712 domain parameters present on every EVM entry
  • x402 v2 envelope delivered in the payment-required header

SITE PILLARS

  • homepage reachable
  • openapi doc
  • pricing page
  • llms.txt
  • robots.txt
  • terms page
recent checks (18) live · click to expand
TIME STATUS RESP CAUSE
● OK 568ms
● OK 622ms
● OK 414ms
● OK 363ms
● OK 339ms
● OK 427ms
● SLOW 677ms
● OK 207ms
● OK 364ms
● OK 416ms
● OK 269ms
● OK 475ms
● OK 239ms
● OK 278ms
● OK 577ms
● OK 590ms
● OK 322ms
● OK 428ms

EMBED THIS BADGE

Show that Circadian is monitored on x402-list. Paste this on your site or README, it links back to this live listing.

Circadian listed on x402-list
status
Circadian uptime on x402-list
live uptime
// HTML
<a href="https://x402-list.com/services/circadian?utm_source=badge&utm_medium=referral&utm_campaign=embed">
  <img src="https://x402-list.com/badge/circadian.svg" alt="Circadian listed on x402-list" height="28">
</a>
// Markdown
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// HTML · live uptime variant
<a href="https://x402-list.com/services/circadian?utm_source=badge&utm_medium=referral&utm_campaign=embed">
  <img src="https://x402-list.com/badge/circadian.svg?data=uptime" alt="Circadian uptime on x402-list" height="28">
</a>

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 ]

Earn the verified tier: x402list pays a real call to this endpoint and, if it delivers, the service is delivery-verified. The fee covers the cost of the probe, not the badge; there is no refund if the call does not deliver. Agent and API only, no in-browser signing. See /api.

[ verify this service ($0.25) ]

To request delisting, email info@x402-list.com or update your listing at /services/circadian/update.