WritersLogic Verifiable AI Agent Hub Symbol Exists API
The Symbol Exists API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for symbol exists.
Work with this as data
Every API here is available over the APIs.io API and to AI agents over MCP.
MCP server
One button, every client — Claude, Cursor, VS Code and the rest.
https://apis.io/mcp
Tools for apis
7 MCP tools reach this
find_apisBrowse and filter every API in the catalog.get_api_artifactsOne API's artifacts, grouped by type.get_openapiThe primary OpenAPI for this API.find_similar_apisAPIs that look like this one.apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.resolveTurn a domain, URL or GitHub org into the provider it belongs to.find_cohortsEvery scored population of providers in the catalog.
Call it yourself
curl for this page
This API
curl "https://apis.io/api/v1/apis/writerslogic-com:writerslogic-com-symbol-exists-api"
All apis
curl "https://apis.io/api/v1/apis?limit=25"Calls without X-API-Key need no key. Calls with it need a paid plan — get a key.
Get an API key
Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.
A second provider on the same verified email joins the account you already have.
OpenAPI Specification
openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Symbol Exists 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: Symbol Exists
paths:
/api/v1/symbol-exists:
post:
operationId: symbol_exists
summary: Is this export in the npm package's published type declarations
description: 'Checks that up to 20 named exports (functions, classes, constants, types, default) exist in the .d.ts files published for an exact npm package version, read from jsDelivr, for coding agents that may be calling an API that does not exist. Follows export lists and relative export-star re-exports within the package (at most 7 files) and reports when the export surface cannot be fully enumerated. Never downloads or runs the package code; packages typed only through @types or without declarations return unsupported; does not check signatures or arguments.
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/symbol-exists
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- package
- version
- symbols
properties:
package:
type: string
maxLength: 214
description: npm package name.
version:
type: string
maxLength: 64
description: Exact version or dist-tag (jsDelivr resolves it).
pattern: ^[0-9A-Za-z.+_~-]{1,64}$
symbols:
type: array
minItems: 1
maxItems: 20
items:
type: string
maxLength: 100
pattern: ^[A-Za-z_$][A-Za-z0-9_$]*$
entry:
type: string
maxLength: 100
description: package.json exports key, default '.'.
typesPath:
type: string
maxLength: 200
description: Declaration file path inside the package, overriding package.json resolution.
example:
package: nanoid
version: 5.0.7
symbols:
- nanoid
- customAlphabet
- nonexistentFn
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.'
package:
type: string
version:
type: string
complete:
type: boolean
description: True when the whole export surface was enumerated, so a missing symbol is a real absence.
filesRead:
type: array
items:
type: string
incomplete:
type: array
items:
type: string
symbols:
type: array
items:
type: object
properties:
symbol:
type: string
found:
type: boolean
kind:
type: string
file:
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:
- Symbol Exists
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