x402-signature-service
Infrastructure PAYMENT-READYpayment-ready until 2026-08-20
Send one PDF to one email recipient for simple electronic signature. The service emails the signer, tracks completion, and returns the completed signed PDF. Gives AI agents the missing capability to get human sign-off on contracts and NDAs: pay $0.50 USDC per request (x402 exact scheme on Base), poll a status URL with a one-time bearer token, download the signed document. SSRF-guarded document fetching, tokens stored as hashes, emails masked in logs.
Pay from $0.50 per request in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.
first settlement 2026-07-17 · $0.71 all-time · settled via coinbase, payAI
ASSESSMENT
updated 1h agoEvidence-backed signals, not a single score. Click any chip for the proof. Measured values stay read-only; unknown is honest.
reliability 99.9%
- uptime 24h
- 100%
- uptime 7d
- 99.8%
- uptime 30d
- 99.9%
- uptime 90d
- 99.9%
- response p95
- 2518ms
- avg response
- 1257ms
- total checks
- 1,458
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.
price $0.50 (p75 in Infrastructure)
- price (min)
- $0.50
- category percentile (min)
- p75 in Infrastructure
- endpoints / prices
- 1 / 1
- model
- flat
- 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
- 23d
- registrar
- Spaceship, Inc.
- hosting
- custom
- domain created
- 2026-07-19
Identity facts, not a risk score.
traction $0.7195 30d · 11 buyers
- volume 30d
- $0.7195
- buyers 30d
- 11
- settlements 30d
- 34
- first settlement
- 2026-07-17
- last settlement
- 2026-08-13
- top buyer share
- 36% of 30d volume
- trend 7d vs 30d
- 0.04x the 30d daily rate
- networks
- eip155:8453
- volume all-time
- $0.71
- settlements all-time
- 34
- median settlement 30d
- $0.01
- max settlement 30d
- $0.50
- settled via
- coinbase ($1.42, 33 tx), payAI ($0.02, 1 tx)
Attributed pro-quota: this payout address is shared, so volume is the operator-level figure divided by the services sharing it, while buyer and transaction counts stay whole. A declared convention, not an individually observed measure, and still a conservative undercount.
Currently sharing this payout address with DeFi Signals API.
Top buyer share is a concentration signal, not part of the ranking score.
WHAT IT DOES
ai-derivedProvides electronic signature services for PDF documents
- category
- electronic-signature
- in
- body
AI-generated summary. The measured data is never altered by it.
ENDPOINTS
| METHOD | PATH | DESCRIPTION | PRICE | NETWORK | ASSET | 402 CHANNEL |
|---|---|---|---|---|---|---|
| GET | /v1/signature-requests | $0.50 | Base | USDC | header |
REQUEST / RESPONSE EXAMPLE
An unpaid request to GET /v1/signature-requests returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.
curl -i 'https://signx402.com/v1/signature-requests'
// 402 response (captured by monitor) · 1 payload · click to expand
[
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xE72b85A97A6e19413D8b80633787Eda6d6237A77",
"amount": "500000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://signx402.com/v1/signature-requests",
"tags": [
"signature",
"e-signature",
"pdf",
"documents",
"contracts",
"workflow"
],
"mimeType": "application/json",
"description": "Send one PDF to one email recipient for simple electronic signature. The service emails the signer, tracks completion, and returns the completed signed PDF. Give an AI agent the missing capability to get human sign-off: submit a contract, NDA or agreement by URL or base64, the recipient signs in the browser (powered by Documenso), and the agent polls a status URL with a one-time bearer token until the signed document is ready for download. Simple electronic signatures (SES) only — no QES/AES, no identity verification, no legal advice. Documents are processed in memory; signer emails are masked in logs.",
"serviceName": "x402-signature-service"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"signer": {
"name": "Anna Müller",
"email": "[email protected]"
},
"message": "Please review and sign this agreement.",
"documentUrl": "https://example.com/agreement.pdf",
"documentName": "Service Agreement",
"expiresInDays": 14,
"externalReference": "customer-contract-4821"
},
"type": "http",
"method": "GET",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"id": "sigreq_1f4a9c2b7d3e8a01",
"signer": {
"name": "Anna Müller",
"email": "a***@example.com"
},
"status": "sent",
"createdAt": "2026-07-19T15:00:00Z",
"expiresAt": "2026-08-02T15:00:00Z",
"statusUrl": "https://your-api.example.com/v1/signature-requests/sigreq_1f4a9c2b7d3e8a01",
"accessToken": "sec_… (plain-text bearer token, shown exactly once)",
"documentName": "Service Agreement"
}
}
},
"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",
"oneOf": [
{
"not": {
"required": [
"documentBase64"
]
},
"required": [
"documentUrl"
]
},
{
"not": {
"required": [
"documentUrl"
]
},
"required": [
"documentBase64"
]
}
],
"required": [
"documentName",
"signer"
],
"properties": {
"signer": {
"type": "object",
"required": [
"name",
"email"
],
"properties": {
"name": {
"type": "string",
"maxLength": 120,
"minLength": 1
},
"email": {
"type": "string",
"format": "email"
}
}
},
"message": {
"type": "string",
"maxLength": 2000,
"description": "Optional message included in the signature request email"
},
"documentUrl": {
"type": "string",
"description": "HTTPS URL of the PDF to sign (max 5 MB). Provide either documentUrl OR documentBase64."
},
"documentName": {
"type": "string",
"maxLength": 150,
"minLength": 1,
"description": "Human-readable document title shown to the signer"
},
"expiresInDays": {
"type": "integer",
"default": 14,
"maximum": 30,
"minimum": 1,
"description": "Days until the signature request expires"
},
"documentBase64": {
"type": "string",
"description": "Base64-encoded PDF (max 5 MB decoded). Provide either documentUrl OR documentBase64."
},
"externalReference": {
"type": "string",
"maxLength": 200,
"description": "Optional caller-side reference id, echoed back in responses"
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"id",
"status",
"statusUrl",
"accessToken"
],
"properties": {
"id": {
"type": "string"
},
"signer": {
"type": "object",
"properties": {
"name": {
"type": "string"
},
"email": {
"type": "string",
"description": "masked, e.g. a***@example.com"
}
}
},
"status": {
"enum": [
"sent",
"viewed",
"completed",
"declined",
"expired",
"error"
],
"type": "string"
},
"createdAt": {
"type": "string"
},
"expiresAt": {
"type": "string"
},
"statusUrl": {
"type": "string",
"description": "Poll this URL with 'Authorization: Bearer <accessToken>' to track progress; append /document once completed to download the signed PDF."
},
"accessToken": {
"type": "string",
"description": "One-time plain-text bearer token for statusUrl and document download. Store it — it is never shown again."
},
"documentName": {
"type": "string"
}
}
}
}
}
}
}
}
},
"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/x402-signature-service/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.
checklist grew 11->14 on 2026-07-28; a step here is a metric change, not a regression
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.
Shared payout address (1 other service). These bars are the full shared address (operator-level), so do not sum them across the services that share it. Where a per-service figure is attributed, the assessment block and the ranking, it is the address total divided pro-quota by the 2 services sharing it: a declared convention, not an individually observed measure.
Shared payout address (1 other service). These bars are the full shared address (operator-level), so do not sum them across the services that share it. Per-service buyer and transaction counts are shown whole (integers), not divided; only volume is attributed pro-quota. A declared convention, not an individually observed measure.
COMPLIANCE
14/14 checks pass · grade Alast 402 captured 2026-07-28 · last up 2026-08-13
- 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
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