The Resolve Prefix API from CrawlCheck — 1 operation(s) for resolve prefix.
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openapi: 3.2.0
info:
title: Crawlcheck Io Resolve Prefix 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 Resolve Prefix 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: Resolve Prefix
paths:
/api/v1/resolve-prefix/{prefix}:
get:
operationId: resolvePrefixV1
summary: 'Private lookup: send 2-8 hex characters of sha256(domain) and receive every…'
parameters:
- name: prefix
in: path
required: true
schema:
type: string
pattern: ^[0-9a-f]{2,8}$
responses:
'200':
description: crawlcheck-resolve-prefix
content:
application/json:
examples:
worked:
summary: Shape with one answer (the signed ResolveV1 document shortened); not a measurement.
value:
kind: crawlcheck-resolve-prefix
v: 1
prefix: a3
generated_at: '2026-10-08T07:00:00.000Z'
reading: Every measured domain whose sha256(domain) starts with this prefix, each with its full signed ResolveV1 answer. Hash your domain locally and pick your match; if none matches, CrawlCheck holds no public measurement of it. Nothing in this request names your domain.
hash: sha256 hex of the domain lowercased, with no scheme, no leading www. and no path or port
in_bucket: 1
answered: 1
left_out: 0
k_note: 'Privacy grows with the number of domains sharing the prefix: 2 hex characters put about 40 measured domains in each bucket today. Longer prefixes return fewer answers and tell CrawlCheck more.'
index:
snapshot: 2026-10-07-3fa91c
built_at: '2026-10-07T21:17:40.000Z'
domains: 10240
answers:
- domain_sha256: a379a6f6eeafb9a55e378c118034e2751e682fab9f2d30ab13d2125586ce1947
answer:
kind: crawlcheck-resolve
v: 1
domain: example.com
status: measured
sha256: …
signature:
alg: Ed25519
kid: …
verify: 'each answers[].answer verifies on its own: node crawlcheck-verify.mjs answer.json'
docs: https://crawlcheck.io/docs/api#resolve-prefix
schema:
type:
- object
- 'null'
properties:
kind:
type:
- string
- 'null'
v:
type:
- number
- 'null'
prefix:
type:
- string
- 'null'
generated_at:
type:
- string
- 'null'
reading:
type:
- string
- 'null'
hash:
type:
- string
- 'null'
in_bucket:
type:
- number
- 'null'
answered:
type:
- number
- 'null'
left_out:
type:
- number
- 'null'
k_note:
type:
- string
- 'null'
index:
type:
- object
- 'null'
properties:
snapshot:
type:
- string
- 'null'
built_at:
type:
- string
- 'null'
domains:
type:
- number
- 'null'
additionalProperties: true
answers:
type:
- array
- 'null'
items:
type:
- object
- 'null'
properties:
domain_sha256:
type:
- string
- 'null'
answer:
type:
- object
- 'null'
properties:
kind:
type:
- string
- 'null'
v:
type:
- number
- 'null'
domain:
type:
- string
- 'null'
status:
type:
- string
- 'null'
sha256: {}
signature:
type:
- object
- 'null'
properties:
alg:
type:
- string
- 'null'
kid: {}
additionalProperties: true
additionalProperties: true
additionalProperties: true
verify:
type:
- string
- 'null'
docs:
type:
- string
- 'null'
additionalProperties: true
x-schema-source: worked-example
'413':
description: more than 100 answers share the prefix; send a longer one
'503':
description: the index is built when the first daily snapshot finishes
x-codeSamples:
- lang: Shell
label: curl
source: h=$(printf '%s' example.com | sha256sum | cut -c1-2); curl -s "https://crawlcheck.io/api/v1/resolve-prefix/$h"
security: []
x-auth: public; no credential read
tags:
- Resolve Prefix
servers:
- url: https://crawlcheck.io
components:
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