The Schema Compat API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for schema compat.
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openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Schema Compat API
version: 2.0.0
description: Pay-per-call agents settled in USDC on Base via x402. Every response carries a signed provenance envelope.
contact:
name: WritersLogic
url: https://writerslogic.com/agents
email: agents@writerslogic.com
servers:
- url: https://agents.writerslogic.com
tags:
- name: Schema Compat
paths:
/api/v1/schema-compat:
post:
operationId: schema_compat
summary: Breaking-change diff between two JSON Schemas or OpenAPI documents, and whether…
description: 'Compares an old and a new JSON Schema 2020-12 (or two OpenAPI 3.0/3.1 documents) and lists each change with its path, keyword, old and new value, whether it narrows or widens what is accepted, and whether it breaks clients: newly required properties, removed or retyped properties, removed enum values, tightened limits, additionalProperties flips, removed operations, removed or newly required parameters, removed media types and responses. Role request (default) treats narrowing as breaking; role response treats widening and removed required fields as breaking. You may also pass cached tool-call arguments: each is validated against the old and the new schema, so a call that worked before and fails now is reported with the failing JSON pointer. Changes it cannot prove either way (pattern rewrites, not/if/then, mixed oneOf edits) are reported as uncomparable and the status is unsupported rather than pass.
Price: 0.005 USDC on Base (x402).'
x-x402-price-usdc: '0.005'
x-x402-amount: '5000'
x-payment-info:
protocols:
- x402
price:
mode: fixed
currency: USD
amount: '0.005'
x-audience: developer
x-sample-url: https://agents.writerslogic.com/api/v1/samples/schema-compat
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- before
- after
- kind
properties:
before:
description: The old schema, or old OpenAPI document. Full JSON Schema 2020-12 (local $ref only).
after:
description: The new schema, or new OpenAPI document. Full JSON Schema 2020-12 (local $ref only).
kind:
type: string
enum:
- json-schema
- openapi
role:
type: string
enum:
- request
- response
description: 'json-schema only: request (default) or response; OpenAPI compares each side in its own role.'
calls:
type: array
maxItems: 50
items:
type: object
additionalProperties: false
required:
- arguments
properties:
name:
type: string
maxLength: 80
arguments:
description: 'Cached call arguments (JSON schema: validated against the root; OpenAPI: against the operation''s JSON request body).'
operation:
type: object
additionalProperties: false
required:
- path
- method
properties:
path:
type: string
maxLength: 500
method:
type: string
enum:
- get
- put
- post
- delete
- options
- head
- patch
- trace
example:
kind: json-schema
before:
type: object
required:
- id
properties:
id:
type: integer
mode:
enum:
- fast
- slow
note:
type: string
after:
type: object
required:
- id
- region
properties:
id:
type: integer
mode:
enum:
- fast
note:
type: string
maxLength: 10
region:
type: string
calls:
- name: cached
arguments:
id: 1
mode: slow
responses:
'200':
description: Paid result with provenance
content:
application/json:
schema:
type: object
properties:
data:
type: object
properties:
status:
type: string
enum:
- pass
- fail
- unknown
- unsupported
description: 'pass: every rule held. fail: a rule was violated (see witnesses). unknown: the input lacks the evidence to decide. unsupported: outside what this engine covers. Missing evidence is never a pass.'
changes:
type: array
items:
type: object
properties:
operation:
type: string
description: 'OpenAPI only: METHOD /path.'
path:
type: string
description: JSON pointer into the schema (json-schema) or into the operation (openapi).
keyword:
type: string
effect:
type: string
enum:
- narrows
- widens
- changed
- uncomparable
- neutral
breaking:
type: boolean
before:
description: Old value.
after:
description: New value.
detail:
type: string
counts:
type: object
properties:
breaking:
type: integer
uncomparable:
type: integer
nonBreaking:
type: integer
operationsCompared:
type: integer
calls:
type: array
items:
type: object
properties:
index:
type: integer
name:
type: string
before:
type: string
enum:
- valid
- invalid
- unknown
after:
type: string
enum:
- valid
- invalid
- unknown
regression:
type: boolean
description: Valid before, invalid after.
errors:
type: array
items:
type: object
properties:
instancePath:
type: string
keyword:
type: string
message:
type: string
witnesses:
type: array
items:
type: object
properties:
ruleId:
type: string
detail:
type: string
path:
type: string
description: JSON pointer or dotted path into the input.
offset:
type: integer
index:
type: integer
expected:
description: What the rule required.
actual:
description: What the input had.
versions:
type: object
description: Every semantic dependency of this answer (engine, tables and their as-of dates, tokenizer, calendar, rounding profile).
limits:
type: array
items:
type: string
deterministic:
type: boolean
description: 'Always true: pure code, no model.'
_provenance:
type: object
description: C2PA-aligned manifest and W3C VC 2.0 (eddsa-jcs-2022) issued by the hub DID; verify at POST /api/v1/verify-provenance
required:
- data
- _provenance
'400':
description: Invalid request (no payment consumed)
content:
application/json:
schema:
type: object
properties:
error:
type: string
code:
type: string
'401':
description: Invalid X-API-KEY
content:
application/json:
schema:
type: object
properties:
error:
type: string
code:
type: string
'402':
description: Payment required or invalid
content:
application/json:
schema:
type: object
description: x402 v2 PaymentRequired (also base64 in the PAYMENT-REQUIRED header)
properties:
x402Version:
type: integer
error:
type: string
code:
type: string
resource:
type: object
accepts:
type: array
items:
type: object
extensions:
type: object
'502':
description: Upstream failure; the payment is released or not settled
content:
application/json:
schema:
type: object
properties:
error:
type: string
code:
type: string
tags:
- Schema Compat
components:
securitySchemes:
x402:
type: apiKey
in: header
name: PAYMENT-SIGNATURE
description: x402 v2 payment payload (base64) sent after a 402 challenge
apiKey:
type: apiKey
in: header
name: X-API-KEY