The Proration API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for proration.
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openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Proration 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: Proration
paths:
/api/v1/proration:
post:
operationId: proration
summary: Proration and day-count fractions (30/360, ACT/365F, ACT/360, ACT/ACT ISDA) on…
description: 'Computes the year fraction of up to 100 half-open date ranges [start, end) under a named ISDA day-count convention, and optionally the prorated charge, for an agent billing a partial period or accruing interest. Conventions follow Section 4.16 of the 2006 ISDA Definitions: 30/360, 30E/360, 30E/360 (ISDA), Actual/365 (Fixed), Actual/360, Actual/Actual (ISDA), 1/1. `end` is the day immediately following the last day included, as the ISDA text defines it. With `period` the charge is amount x fraction(range) / fraction(period), the usual subscription proration. 30E/360 (ISDA) with a range ending on the last day of February needs terminationDate, else unknown. Actual/Actual (ICMA) is unsupported. Not a calendar-month proration policy and not the 2021 ISDA Definitions.
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/proration
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- items
properties:
items:
type: array
minItems: 1
maxItems: 100
items:
type: object
required:
- start
- end
- convention
properties:
start:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: Calendar date YYYY-MM-DD.
end:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: 'Exclusive end: the day after the last day included. Must not precede start.'
convention:
type: string
enum:
- 1/1
- 30/360
- 30E/360
- 30E/360-ISDA
- ACT/365F
- ACT/360
- ACT/ACT-ISDA
- ACT/ACT-ICMA
terminationDate:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: Termination date of the transaction; only used by 30E/360-ISDA.
amount:
type: string
pattern: ^-?\d{1,15}(\.\d{1,12})?$
maxLength: 30
description: Optional amount to prorate (annual amount without `period`; period amount with it).
currency:
type: string
pattern: ^[A-Z]{3}$
description: ISO 4217 alphabetic code, upper case.
exponent:
type: integer
minimum: 0
maximum: 8
rounding:
type: string
enum:
- half-up
- half-down
- half-even
- up
- down
- ceiling
- floor
description: 'Rounding of the charge to the currency''s minor unit. Default half-up. half-up: ties away from zero. half-down: ties toward zero. half-even: ties to the even neighbour. up: away from zero. down: toward zero. ceiling: toward +infinity. floor: toward -infinity.'
period:
type: object
required:
- start
- end
properties:
start:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: Calendar date YYYY-MM-DD.
end:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: Calendar date YYYY-MM-DD.
description: Full billing period [start, end); the charge is amount x fraction(range) / fraction(period).
additionalProperties: false
additionalProperties: false
example:
items:
- start: '2003-11-01'
end: '2004-05-01'
convention: ACT/ACT-ISDA
amount: '1000.00'
currency: USD
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.'
items:
type: array
items:
type: object
properties:
index:
type: integer
status:
type: string
enum:
- pass
- fail
- unknown
- unsupported
fraction:
type: string
description: Year fraction to 15 decimal places (half-even); the charge uses the unrounded value.
days:
type: integer
description: Actual calendar days in [start, end).
detail:
type: string
description: Numerator and divisor, e.g. 61/365 + 121/366.
periodFraction:
type: string
charge:
type: string
description: Prorated amount at the currency's precision.
chargeMinor:
type: integer
exponent:
type: integer
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:
- Proration
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