WritersLogic Verifiable AI Agent Hub Idempotency Registry API
The Idempotency Registry API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for idempotency registry.
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curl "https://apis.io/api/v1/apis/writerslogic-com:writerslogic-com-idempotency-registry-api"
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OpenAPI Specification
openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Idempotency Registry…
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: Idempotency Registry
paths:
/api/v1/idempotency-registry:
post:
operationId: idempotency_registry
summary: 'Idempotency registry: has key K already been done?'
description: 'Shared memory for side-effecting operations across agents and retries. begin(key) answers proceed (you hold a short claim), wait (another owner is mid-flight), already_completed (returns the stored result pointer), or fingerprint_mismatch (same key, different operation). complete(key) records the result pointer; abandon(key) lets someone retry. The claim expires, so a crashed worker does not block the key forever. Never infers completion from a timeout: only complete() marks a key done.
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: agent-infra
x-sample-url: https://agents.writerslogic.com/api/v1/samples/idempotency-registry
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- op
- key
properties:
op:
type: string
enum:
- begin
- complete
- abandon
- get
key:
type: string
pattern: ^[A-Za-z0-9_.:/@+-]{1,200}$
description: Idempotency key, e.g. refund:ch_123:2026-11-04.
owner:
type: string
minLength: 1
maxLength: 128
description: Worker id; required for begin, complete and abandon.
fingerprint:
type: string
minLength: 1
maxLength: 128
description: Hash of the operation's identity fields; a later begin with a different fingerprint is refused.
claimSeconds:
type: integer
minimum: 1
maximum: 3600
description: How long a begin claim lasts; default 300.
retentionHours:
type: integer
minimum: 1
maximum: 168
description: How long a completed key is remembered; default 24.
result:
type: object
additionalProperties: false
description: 'complete: where the outcome lives (do not store payloads here).'
properties:
pointer:
type: string
maxLength: 500
digest:
type: string
maxLength: 128
summary:
type: string
maxLength: 500
tenantId:
type: string
pattern: ^[A-Za-z0-9_.-]{1,64}$
description: 'Required for API-key callers (namespaced as key:<tenantId>; keep it unguessable). Ignored when a wallet paid: the payer address is the tenant.'
requestId:
type: string
pattern: ^[A-Za-z0-9_.:-]{1,128}$
description: 'Caller-chosen id for this mutation. A retry with the same id and same input returns the stored response (24 h) instead of applying twice; the same id with different input is rejected. Send one on every mutation you may retry: without it a retry is applied again (fleet-memory record appends a duplicate; a repeated spend-ledger commit or release answers NO_HOLD because the first call already took effect).'
example:
op: begin
key: refund:ch_3Q1:2026-11-04
owner: billing-agent-2
fingerprint: sha256:4be1…
requestId: ba2-refund-ch_3Q1
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.'
op:
type: string
decision:
type: string
enum:
- proceed
- wait
- already_completed
- fingerprint_mismatch
- recorded
- not_owner
- none
state:
anyOf:
- type: string
description: in_progress, completed, abandoned, or null when the key is unknown.
- type: 'null'
description: in_progress, completed, abandoned, or null when the key is unknown.
owner:
anyOf:
- type: string
- type: 'null'
claimExpiresAt:
anyOf:
- type: string
- type: 'null'
completedAt:
anyOf:
- type: string
- type: 'null'
stored:
anyOf:
- type: object
description: The result recorded by complete().
- type: 'null'
description: The result recorded by complete().
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:
- Idempotency Registry
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