The Recurrence Expand API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for recurrence expand.
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openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Recurrence Expand 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: Recurrence Expand
paths:
/api/v1/recurrence-expand:
post:
operationId: recurrence_expand
summary: Expand an RRULE or 5-field cron into concrete occurrences with DST handling…
description: 'Expands an RFC 5545 RRULE (FREQ DAILY/WEEKLY/MONTHLY/YEARLY, INTERVAL, COUNT, UNTIL, BYDAY with ordinals, BYMONTHDAY, BYMONTH, BYSETPOS, WKST; DTSTART with TZID; EXDATE) or a crontab(5) expression into up to 366 occurrences in a time zone, with the UTC instant of each, DST gap or overlap flags, caller blackout dates, a plain-English reading, and optionally the occurrences where it collides with a second rule. COUNT is applied before EXDATE removal, invalid dates (Feb 30) are skipped, a time in a gap is read with the pre-gap offset and an overlap uses its first occurrence (RFC 5545 3.3.5). Hourly/minutely FREQ, BYHOUR, BYYEARDAY, BYWEEKNO, RDATE, EXRULE, Quartz cron extensions and @macros return `unsupported`. Never reads the clock: the window starts at `from` (or DTSTART).
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: business
x-sample-url: https://agents.writerslogic.com/api/v1/samples/recurrence-expand
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- kind
- rule
properties:
kind:
type: string
enum:
- rrule
- cron
rule:
type: string
maxLength: 800
description: 'rrule: ''DTSTART;TZID=America/New_York:19970902T090000\nRRULE:FREQ=DAILY;COUNT=10\nEXDATE;TZID=America/New_York:19970903T090000'' or just ''FREQ=...'' with dtstart. cron: ''*/15 9-17 * * 1-5'' (dom and dow both restricted match if either does).'
dtstart:
type: string
pattern: ^\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}(:\d{2}(\.\d{1,9})?)?$
maxLength: 30
description: Local DTSTART when the rule text has none.
timeZone:
type: string
pattern: ^[A-Za-z][A-Za-z0-9_+-]*(/[A-Za-z0-9_+-]+){0,2}$
maxLength: 64
description: IANA zone for local times (required for cron; for rrule unless DTSTART has TZID or Z).
from:
type: string
pattern: ^\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}(:\d{2}(\.\d{1,9})?)?$
maxLength: 30
description: Local start of the output window; required for cron, default DTSTART for rrule.
to:
type: string
pattern: ^\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}(:\d{2}(\.\d{1,9})?)?$
maxLength: 30
description: Local end of the window, inclusive.
limit:
type: integer
minimum: 1
maximum: 366
description: Maximum occurrences returned (default 20).
exdates:
type: array
maxItems: 200
items:
type: string
maxLength: 30
description: Extra excluded local date-times (YYYY-MM-DDTHH:MM[:SS]) or dates (YYYY-MM-DD, excludes that day).
blackouts:
type: array
maxItems: 50
items:
type: object
required:
- start
- end
properties:
start:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
end:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
description: Inclusive local date ranges to drop (holidays, freezes).
durationMinutes:
type: integer
minimum: 0
maximum: 43200
description: Occurrence length, for conflict overlap.
other:
type: object
required:
- kind
- rule
description: A second rule to compare; conflicts are occurrences whose intervals overlap (equal instants when both durations are 0).
properties:
kind:
type: string
enum:
- rrule
- cron
rule:
type: string
maxLength: 800
dtstart:
type: string
pattern: ^\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}(:\d{2}(\.\d{1,9})?)?$
maxLength: 30
timeZone:
type: string
pattern: ^[A-Za-z][A-Za-z0-9_+-]*(/[A-Za-z0-9_+-]+){0,2}$
maxLength: 64
durationMinutes:
type: integer
minimum: 0
maximum: 43200
example:
kind: rrule
rule: 'DTSTART;TZID=America/New_York:19970902T090000
RRULE:FREQ=DAILY;COUNT=10'
limit: 10
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.'
occurrences:
type: array
items:
type: object
properties:
index:
type: integer
local:
type: string
utc:
type: string
dst:
type: string
enum:
- gap
- overlap
count:
type: integer
description:
type: string
timeZone:
type: string
excluded:
type: array
items:
type: object
properties:
local:
type: string
reason:
type: string
moreAvailable:
type: boolean
scanCapped:
type: boolean
conflicts:
type: array
items:
type: object
properties:
aIndex:
type: integer
bIndex:
type: integer
aUtc:
type: string
bUtc:
type: string
comparedThroughUtc:
type: string
reason:
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:
- Recurrence Expand
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