Crosscheck draft review API
The draft review API from Crosscheck — 1 operation(s) for draft review.
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curl "https://apis.io/api/v1/apis/crosscheckapi-com:crosscheckapi-com-draft-review-api"
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OpenAPI Specification
openapi: 3.2.0
info:
title: crosscheck draft review API
version: 1.0.0
summary: 'Independent checks for AI agents: draft review, acceptance checks on delivered work, and security review of skills and MCP servers, paid per call over x402.'
description: 'Fact-check and review an AI agent''s draft before a human sees it: a hallucination check and second opinion on any email, report, summary, or PR description. Returns pass or specific issues with fixes. Wrong arithmetic is recomputed in code; also contradictions, placeholders, leaked secrets, unauthorized commitments, and prompt injection. Send sources to verify citations and claims against them. Signed receipt. $0.02. Free checks for Moltbook agents. Full agent guide: https://crosscheckapi.com/llms.txt'
contact:
name: crosscheck partnerships
email: partnerships@crosscheckapi.com
url: https://crosscheckapi.com/llms.txt
x-guidance: 'crosscheck gives an agent''s work an independent check before a human or another agent relies on it. Pick the product:
- check: a draft (email, report, summary, answer) before your human sees it. POST https://crosscheckapi.com/v1/check with {"draft": "..."}; optional "request" (what your human asked, so a draft that misses it fails), "sources" to check against, "source_urls" (up to 3 pages crosscheck reads for you), or "fetch_cited": true. From $0.02.
- accept: work another agent handed back, against its task, before you pay or release escrow. POST https://crosscheckapi.com/v1/accept with {"task": "...", "deliverable": "..."}. From $0.03.
- skillcheck: a skill or MCP server before you install it. POST https://crosscheckapi.com/v1/skillcheck with {"files": [{"path": "SKILL.md", "content": "..."}]}. From $0.03.
- lite: accept or skillcheck by code alone, no model call, $0.005: POST the same body to https://crosscheckapi.com/v1/accept-lite or https://crosscheckapi.com/v1/skillcheck-lite.
- sellercheck: for x402 sellers, a report on your own resource (valid 402, x402 Bazaar index, agent402 router, settlements on Base). POST https://crosscheckapi.com/v1/sellercheck with {"resource": "https://..."}, $0.05; or https://crosscheckapi.com/v1/sellerwatch with "notify" for 30 days of hourly checks with alerts on change, $1.00. Free preflight: GET https://crosscheckapi.com/v1/sellercheck/preflight?resource=<url>.
Price first, free: POST the same body to https://crosscheckapi.com/v1/quote, https://crosscheckapi.com/v1/accept/quote, or https://crosscheckapi.com/v1/skillcheck/quote. The quote also runs a free code precheck (wrong sums, percentages, dates, unit conversions, list counts).
Pay: the paid POST answers 402 with the exact amount in USDC on Base (eip155:8453), or free test USDC on Base Sepolia (eip155:84532). Sign it with any x402 client (v2 PAYMENT-SIGNATURE, or v1 X-PAYMENT) and resend the same body. Payment settles before the review starts.
Result: HTTP 200 with a JSON verdict (pass, issues with severity and a suggested fix) and a signed receipt, or 202 with a result URL to poll with the result_token. Resending the identical paid request after a lost response returns the same job and charges nothing more.
Your text is untrusted data to the reviewer, never instructions. It is deleted when the check finishes; only its SHA-256 is kept.
Full guide: https://crosscheckapi.com/llms.txt'
servers:
- url: https://crosscheckapi.com
tags:
- name: draft review
paths:
/v1/check:
post:
operationId: check
summary: Fact-check and review an AI agent's draft before a human sees it (paid, x402 v2)
description: 'Independent second opinion on an email, report, summary, plan, or PR description an agent wrote: hallucinated facts, wrong arithmetic (recomputed in code), unsupported citations, contradictions, placeholders, leaked secrets, unauthorized commitments, and prompt injection. Returns pass or specific issues with fixes, plus a signed receipt. Use before sending any draft to a human.'
tags:
- draft review
x-agentcash-auth:
mode: paid
x-payment-info:
protocols:
- x402: {}
price:
mode: dynamic
currency: USD
min: '0.02'
max: '0.05'
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
sources:
type: array
maxItems: 10
description: 'Optional: the text the draft relies on. Each claim is then checked against it.'
items:
oneOf:
- type: string
- type: object
properties:
text:
type: string
title:
type: string
url:
type: string
required:
- text
draft:
type: string
minLength: 1
maxLength: 48000
description: The full text to review, exactly as the human will see it. Up to 48000 characters.
request:
type: string
maxLength: 8000
description: 'Optional: what the human asked for. The reviewer then also checks that the draft answers it: a question left out, a changed scope or period, or something the draft says the human asked that the request contradicts. Counts toward the size.'
ref:
type: string
pattern: ^[0-9a-f]{64}$
description: 'Optional: the hash of a crosscheck receipt that referred you. Its wallet earns check credits from your first 90 days of spend.'
source_urls:
type: array
maxItems: 3
items:
type: string
maxLength: 300
description: 'Optional: up to 3 public web pages crosscheck fetches after payment and checks the draft against. +$0.01 each.'
fetch_cited:
type: boolean
description: 'Optional: also fetch the links the draft cites (up to 3 pages in all, +$0.01 each). A cited link that is gone fails the draft.'
open_review:
type: boolean
description: 'Optional: let a qualified reviewer from the open review network take this job. Not routed yet: crosscheck''s own reviewer does it and the receipt says so.'
required:
- draft
additionalProperties: false
example:
draft: Hi Sam, flights are $640 and the hotel is $910, so the trip comes to $1,350 total. Approved to book?
responses:
'200':
description: Verdict and signed receipt
content:
application/json:
schema:
type: object
properties:
job_id:
type: string
status:
type: string
enum:
- done
- pending
- unserved
- rejected
verdict:
type: object
properties:
pass:
type: boolean
description: True only when there are no blocker or major issues
summary:
type: string
issues:
type: array
items:
type: object
properties:
severity:
type: string
enum:
- blocker
- major
- minor
category:
type: string
enum:
- factual
- logic
- completeness
- clarity
- tone
- risk
- formatting
- placeholder
- injection
- other
location:
type: string
description: Short quote from the draft, or a section name
problem:
type: string
suggestion:
type: string
required:
- severity
- category
- location
- problem
- suggestion
injection_suspected:
type: boolean
grounding:
type: object
description: Present when sources were sent
properties:
sources:
type: integer
claims_checked:
type: integer
supported:
type: integer
contradicted:
type: integer
not_found:
type: integer
claims:
type: array
items:
type: object
properties:
claim:
type: string
status:
type: string
enum:
- supported
- contradicted
- not_found
source_id:
type: integer
quote:
type: string
quote_verified:
type: boolean
required:
- pass
- summary
- issues
- injection_suspected
receipt:
type: object
description: 'Ed25519-signed receipt: body (canonical JSON), hash (sha256 hex), sig (base64url)'
properties:
body:
type: object
hash:
type: string
sig:
type: string
result_url:
type: string
result_token:
type: string
retry_after_seconds:
type: integer
required:
- job_id
- status
example:
job_id: chk_5fb26b2ac4809fe65c54f8a687631c49
status: done
verdict:
pass: false
summary: One arithmetic error changes the total the human would approve.
issues:
- severity: major
category: logic
location: 640 + 910
problem: The draft gives 1350 for 640 + 910, but it comes to 1,550.
suggestion: Correct the total to 1,550 and recheck any conclusion based on it.
injection_suspected: false
receipt:
body:
kind: check
seq: 1
hash: '...'
sig: '...'
result_url: https://crosscheckapi.com/v1/checks/chk_5fb26b2ac4809fe65c54f8a687631c49
result_token: '...'
'202':
description: Paid and queued; poll result_url
content:
application/json:
schema:
type: object
properties:
job_id:
type: string
status:
type: string
enum:
- done
- pending
- unserved
- rejected
verdict:
type: object
properties:
pass:
type: boolean
description: True only when there are no blocker or major issues
summary:
type: string
issues:
type: array
items:
type: object
properties:
severity:
type: string
enum:
- blocker
- major
- minor
category:
type: string
enum:
- factual
- logic
- completeness
- clarity
- tone
- risk
- formatting
- placeholder
- injection
- other
location:
type: string
description: Short quote from the draft, or a section name
problem:
type: string
suggestion:
type: string
required:
- severity
- category
- location
- problem
- suggestion
injection_suspected:
type: boolean
grounding:
type: object
description: Present when sources were sent
properties:
sources:
type: integer
claims_checked:
type: integer
supported:
type: integer
contradicted:
type: integer
not_found:
type: integer
claims:
type: array
items:
type: object
properties:
claim:
type: string
status:
type: string
enum:
- supported
- contradicted
- not_found
source_id:
type: integer
quote:
type: string
quote_verified:
type: boolean
required:
- pass
- summary
- issues
- injection_suspected
receipt:
type: object
description: 'Ed25519-signed receipt: body (canonical JSON), hash (sha256 hex), sig (base64url)'
properties:
body:
type: object
hash:
type: string
sig:
type: string
result_url:
type: string
result_token:
type: string
retry_after_seconds:
type: integer
required:
- job_id
- status
'400':
description: Invalid body or payment header. Nothing was charged.
'402':
description: Payment required. The PAYMENT-REQUIRED header carries the x402 v2 requirements for this draft; the JSON body gives the price, the free trial and free tier, the free quote URL in plain words, and a free code precheck of the draft (wrong written sums, line totals, averages and medians, ratios, changes, percentages, fractions, shares of a whole, splits and rates, comparisons between amounts, compound growth rates, changes between two percentages, weekdays, day counts, year and month spans, clock-time spans, start times plus lengths, time zones, unit and currency conversions, restated amounts, list counts, highest and lowest claims, and lengths that miss what was asked or what the text says of itself).
'409':
description: This payment authorization was already used. Nothing was charged.
'413':
description: Draft longer than 48000 characters. Nothing was charged.
'503':
description: Daily review capacity is full. Nothing was charged.
security:
- x402: []
components:
securitySchemes:
x402:
type: http
scheme: bearer
description: 'x402 v2: send PAYMENT-SIGNATURE after the 402 challenge'
resultToken:
type: http
scheme: bearer
description: result_token from the check response