CrawlCheck Rules API
The Rules API from CrawlCheck — 1 operation(s) for rules.
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curl "https://apis.io/api/v1/apis/crawlcheck-io:crawlcheck-io-rules-api"
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OpenAPI Specification
openapi: 3.2.0
info:
title: Crawlcheck Io Rules API
version: '1'
contact:
name: CrawlCheck
url: https://crawlcheck.io/policy
email: hello@crawlcheck.io
license:
name: Terms
url: https://crawlcheck.io/policy
x-core-contract:
promise: 'These operations are the core contract. They stay at /api/v1 and keep answering for at least 180 days after any /api/v2 is announced; their stable fields change only in a new major version, and their provisional fields only after 30 days'' notice, per /docs/api/compatibility. Verifying what they return needs none of these calls: crawlcheck-verify.mjs checks a document on your machine against the published keys (/.well-known/http-message-signatures-directory) and the rotation record, read once with --online or saved for --keys. Everything else documented here is useful but secondary, and may change with the notice its fields'' tags promise.'
operations:
- method: GET
path: /api/v1/resolve
operationId: resolveDomainV1
- method: POST
path: /api/v1/resolve
operationId: resolveBatchV1
- method: POST
path: /api/v1/preflight
operationId: preflightV1
- method: GET
path: /api/v1/decisions/{sha256}
operationId: decisionCheckV1
- method: GET
path: /api/v1/revocations
operationId: revocations
- method: GET
path: /api/v1/visitor
operationId: visitorResolveV1
- method: POST
path: /api/v1/visitor
operationId: visitorResolveBatchV1
- method: GET
path: /api/v1/mcp/scan
operationId: mcpScanUrl
- method: POST
path: /api/v1/mcp/lock/check
operationId: mcpLockCheck
list: https://crawlcheck.io/api/v1/core
description: 'Operations tagged Rules across 2 of this provider''s published API definitions: crawlcheck-io-openapi.json, crawlcheck-io-openapi.yml. Each path carries the servers of the definition it was published in.'
servers:
- url: https://crawlcheck.io
tags:
- name: Rules
paths:
/api/rules:
get:
operationId: rulebook
summary: 'The rulebook: every finding code CrawlCheck can raise, with what it means, its…'
parameters:
- name: code
in: query
required: false
schema:
type: string
responses:
'200':
description: crawlcheck-rulebook (RulebookV1)
content:
application/json:
schema:
$ref: '#/components/schemas/RulebookV1'
examples:
worked:
summary: Production reads the scan counters live. Without ?code= the rules array carries every rule.
value:
ok: true
kind: crawlcheck-rulebook
v: 1
generated_at: '2026-10-02T03:55:01.445Z'
score_version: 26
schema: https://crawlcheck.io/schemas/rulebook.json
counts:
rules: 63
by_kind:
scan: 52
answer_correlation: 5
capability_mismatch: 6
by_family:
site: 8
headers: 4
mostly_code: 3
machine_files: 11
robots: 13
delivery: 8
jsonld: 3
nap: 2
answers: 5
capabilities: 6
revised: 7
scored: 48
scans_counted: 2518
severity_scale:
- level: info
- level: low
- level: medium
- level: high
- level: critical
method:
revisions: A rule that changes what it reports gets a new revision; a record keeps the revision that decided it, and a replay uses that revision, never today's.
share: Share of counted scans that carried the code at least once, the same numbers /data publishes. Self-scans and opted-out sites are never counted.
grade: Each finding has a level from info to critical. Open findings at medium and above lower the letter grade; fix them first.
rules:
- code: NO_LLMS_TXT
kind: scan
family:
id: machine_files
label: Machine files
title: No llms.txt
meaning: Not a defect. llms.txt is an emerging convention for telling AI systems what a site is and which pages matter.
severity:
level: info
scored: true
measured_on: every scan
revision:
current: 1
revised_at: null
fix:
advice: 'Publish /llms.txt: a short Markdown file naming the business, what it does, and the pages worth reading, served as text/plain or text/markdown.'
effort: content
endpoint: https://crawlcheck.io/api/tool/llms?domain={domain}&format=txt
share_of_scans:
pct: 24.8
scans: 625
of_scans: 2518
basis: share of counted scans that carried it; the same numbers /data publishes
links:
self: https://crawlcheck.io/rules#NO_LLMS_TXT
api: https://crawlcheck.io/api/rules?code=NO_LLMS_TXT
glossary:
- https://crawlcheck.io/glossary/llms-txt
- https://crawlcheck.io/glossary/machine-layer
workflow: https://crawlcheck.io/workflow/NO_LLMS_TXT
lineage: https://crawlcheck.io/docs/lineage-coverage
explain_template: https://crawlcheck.io/api/explain?id={report_id}&code=NO_LLMS_TXT
filter:
code: NO_LLMS_TXT
'404':
description: no rule with that code; the list of codes
x-codeSamples:
- lang: Shell
label: curl
source: curl -s 'https://crawlcheck.io/api/rules?code=NO_LLMS_TXT'
security: []
x-auth: public; no credential read
tags:
- Rules
servers:
- url: https://crawlcheck.io
components:
schemas:
RuleV1:
type: object
required:
- code
- kind
- family
- title
- severity
- revision
- share_of_scans
description: 'One rule: the code, what it means, its level, its current revision, its fix and its share of counted scans.'
properties:
code:
type: string
pattern: ^[A-Z][A-Z0-9_]+$
x-stability: provisional
kind:
enum:
- scan
- answer_correlation
- capability_mismatch
- self_audit
description: 'self_audit: a defect in CrawlCheck''s own record, never in the site'
x-stability: provisional
family:
type: object
required:
- id
- label
properties:
id:
type: string
x-stability: provisional
label:
type: string
x-stability: provisional
x-stability: provisional
title:
type:
- string
- 'null'
x-stability: provisional
meaning:
type:
- string
- 'null'
x-stability: provisional
severity:
type: object
properties:
level:
type:
- string
- 'null'
x-stability: provisional
x-stability: provisional
scored:
type: boolean
description: raised on a graded scan record; refusals, answer runs, capability mismatches and self-audit findings are not
x-stability: provisional
measured_on:
type:
- string
- 'null'
x-stability: provisional
revision:
type: object
required:
- current
properties:
current:
type: integer
minimum: 1
x-stability: provisional
revised_at:
type:
- string
- 'null'
description: when the current revision took effect; null while the rule is at revision 1
x-stability: provisional
x-stability: provisional
fix:
type: object
properties:
advice:
type:
- string
- 'null'
x-stability: provisional
effort:
type:
- string
- 'null'
x-stability: provisional
endpoint:
type:
- string
- 'null'
x-stability: provisional
x-stability: provisional
share_of_scans:
type: object
required:
- pct
- basis
properties:
pct:
type:
- number
- 'null'
x-stability: provisional
scans:
type:
- integer
- 'null'
x-stability: provisional
of_scans:
type:
- integer
- 'null'
x-stability: provisional
basis:
type: string
x-stability: provisional
x-stability: provisional
links:
type: object
properties:
self:
type:
- string
- 'null'
x-stability: provisional
api:
type:
- string
- 'null'
x-stability: provisional
glossary:
type: array
items:
type: string
x-stability: provisional
workflow:
type:
- string
- 'null'
x-stability: provisional
lineage:
type:
- string
- 'null'
x-stability: provisional
explain_template:
type:
- string
- 'null'
x-stability: provisional
x-stability: provisional
x-stability: provisional
RulebookV1:
type: object
required:
- kind
- v
- generated_at
- counts
- severity_scale
- rules
description: 'Every finding CrawlCheck can raise (GET /api/rules): what it means, its level, its fix and its share of counted scans.'
properties:
ok:
type: boolean
x-stability: provisional
kind:
const: crawlcheck-rulebook
x-stability: provisional
v:
const: 1
x-stability: provisional
generated_at:
type: string
x-stability: provisional
score_version:
type:
- number
- 'null'
x-stability: provisional
schema:
type:
- string
- 'null'
x-stability: provisional
counts:
type: object
required:
- rules
properties:
rules:
type: integer
x-stability: provisional
by_kind:
type: object
additionalProperties:
type: integer
x-stability: provisional
by_family:
type: object
additionalProperties:
type: integer
x-stability: provisional
revised:
type: integer
x-stability: provisional
scored:
type: integer
x-stability: provisional
x-stability: provisional
scans_counted:
type:
- integer
- 'null'
x-stability: provisional
severity_scale:
type: array
items:
type: object
properties:
level:
type: string
x-stability: provisional
x-stability: provisional
method:
type: object
properties:
revisions:
type:
- string
- 'null'
x-stability: provisional
share:
type:
- string
- 'null'
x-stability: provisional
grade:
type:
- string
- 'null'
x-stability: provisional
x-stability: provisional
rules:
type: array
items:
$ref: '#/components/schemas/RuleV1'
description: every rule; with ?code= only that rule (counts still describe the whole rulebook)
x-stability: provisional
filter:
type:
- object
- 'null'
properties:
code:
type:
- string
- 'null'
x-stability: provisional
x-stability: provisional
x-stability: provisional
securitySchemes:
licenceKey:
type: apiKey
in: header
name: x-crawlcheck-key
description: 'Your licence key: cc_ followed by 32 hex characters. Sent on every keyed call.'
bearer:
type: http
scheme: bearer
description: The same licence key as a Bearer token. Accepted on /api/v1/* and /api/usage.
externalDocs:
url: https://crawlcheck.io/docs/api
description: Human-readable reference
x-refined-from:
- crawlcheck-io-openapi.json
- crawlcheck-io-openapi.yml