WritersLogic Verifiable AI Agent Hub Precedent Search API
The Precedent Search API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for precedent search.
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OpenAPI Specification
openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Precedent Search 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: Precedent Search
paths:
/api/v1/precedent-search:
post:
operationId: precedent_search
summary: Case-law precedent search (CourtListener, US)
description: 'Finds US court opinions most on point for a legal question or fact pattern: searches CourtListener''s case-law index (optionally limited to courts and filing dates), reads the top opinions, and returns the best matches with a holding passage verified verbatim against the opinion text, plus citation, court, date, precedential status and a source hash. A second skeptical pass flags matches that look off point. It finds precedents for a question; it does not verify citations a brief already contains (use legal-cite-verifier for existence, name, year and quote checks). It is not a citator (no subsequent history or overruling check) and not legal advice. Coverage is limited to CourtListener''s index; abstains with no_precedent_found rather than guessing.
Price: 1.00 USDC on Base (x402).'
x-x402-price-usdc: '1.00'
x-x402-amount: '1000000'
x-payment-info:
protocols:
- x402
price:
mode: fixed
currency: USD
amount: '1.00'
x-audience: legal-ip
x-sample-url: https://agents.writerslogic.com/api/v1/samples/precedent-search
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- question
properties:
question:
type: string
minLength: 20
maxLength: 2000
description: The legal issue and key facts. Quote a phrase to require it verbatim in the search.
courts:
type: array
maxItems: 10
items:
type: string
pattern: ^[a-z0-9]{2,20}$
description: CourtListener court ids such as "scotus", "ca9", "cal", "calctapp". Omit to search all courts.
filed_after:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: Earliest filing date, YYYY-MM-DD.
filed_before:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
description: Latest filing date, YYYY-MM-DD.
max_results:
type: integer
minimum: 1
maximum: 8
description: Default 5.
include_excerpts:
type: boolean
description: Default true. When false, the holding passage text is omitted from the output (quote_verified and quote_offset are still reported).
example:
question: Does a warrantless search of a cell phone seized incident to a lawful arrest violate the Fourth Amendment?
courts:
- scotus
- ca9
max_results: 3
responses:
'200':
description: Paid result with provenance
content:
application/json:
schema:
type: object
properties:
data:
type: object
properties:
status:
type: string
enum:
- ok
- no_precedent_found
question_sha256:
type: string
queries_used:
type: array
items:
type: string
description: Free-text queries sent to CourtListener; court and date filters are applied separately.
courts:
type: array
items:
type: string
precedents:
type: array
items:
type: object
properties:
case_name:
type: string
citations:
type: array
items:
type: string
court:
type: string
court_id:
type: string
date_filed:
type: string
precedential_status:
type: string
cluster_id:
type: integer
opinion_id:
type: integer
opinion_type:
type: string
description: CourtListener type of the opinion read, such as 020lead; a quote from a dissent or concurrence is not the court's holding.
url:
type: string
source_sha256:
type: string
description: SHA-256 of the CourtListener opinions API response the text was derived from.
source_chars:
type: integer
truncated_source:
type: boolean
description: The model saw head and tail halves of an opinion over the character cap; quotes are verified against the full text.
relevance:
type: integer
issue_match:
type: string
enum:
- direct
- analogous
- background
holding_quote:
anyOf:
- type: string
description: Verbatim passage, or null when not verified or include_excerpts is false.
- type: 'null'
quote_verified:
type: boolean
quote_offset:
anyOf:
- type: integer
description: UTF-16 offset of the quote in the NFC form of the full opinion text; null when unverified.
- type: 'null'
why_relevant:
type: string
challenged:
anyOf:
- type: string
description: Reason a skeptical second pass thought the opinion off point, or null.
- type: 'null'
candidates_seen:
type: array
items:
type: object
description: case_name, cluster_id, court_id, date_filed, text_read for every search candidate.
llm:
type: object
description: selection {provider, model} (null when no model call was needed) and adversarial ok|unavailable|skipped.
not_a_citator:
type: boolean
notice:
type: string
limits:
type: object
_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:
- Precedent Search
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