WritersLogic Verifiable AI Agent Hub Magic Bytes API
The Magic Bytes API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for magic bytes.
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OpenAPI Specification
openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Magic Bytes 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: Magic Bytes
paths:
/api/v1/magic-bytes:
post:
operationId: magic_bytes
summary: File type vs leading bytes (magic numbers, disguised HTML, truncation)
description: 'Compares a claimed file type (MIME type and/or file name) with the first bytes of the file, for an agent that is about to open, parse or forward a download. Detects PNG, JPEG, GIF, WebP, ZIP and OOXML (docx/xlsx/pptx), GZIP, PDF, MP4 (ftyp), ELF, PE, RAR, BMP, ICO and HTML, flags an HTML login or error page saved as a PDF/image/archive, and reports truncation from end-of-file markers when the last bytes or the total size are supplied. Input is base64 of up to 32 KiB of head bytes and optionally 4 KiB of tail bytes. It does not decompress, validate image data, scan for malware, or prove a file is safe; a pass means the signature and the structural markers it could see are consistent with the claim.
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/magic-bytes
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- head
properties:
head:
type: string
maxLength: 43692
description: Standard padded base64 of the first bytes of the file (up to 32768 bytes decoded).
tail:
type: string
maxLength: 5464
description: Optional base64 of the last bytes (up to 4096 decoded), used for end-of-file markers when head is not the whole file.
totalSize:
type: integer
minimum: 0
maximum: 1000000000000
description: Optional total file size in bytes, for size-field comparisons (RIFF, MP4 boxes, ZIP directory).
complete:
type: boolean
description: True when head is the entire file; end-of-file markers are then checked on it.
claimedName:
type: string
maxLength: 255
description: File name or path; the last extension is the claim.
claimedMime:
type: string
maxLength: 255
description: Claimed Content-Type, parameters ignored.
example:
head: iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAElFTkSuQmCC
complete: true
claimedName: logo.png
claimedMime: image/png
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.'
detected:
anyOf:
- type: object
properties:
kind:
type: string
mime:
type: string
offset:
type: integer
subtype:
type: string
details:
description: Format-specific facts such as ZIP entry names or the PE machine.
- type: 'null'
description: Detected format {kind, mime, offset, subtype?, details?}, or null when no signature matched.
claimed:
type: array
items:
type: object
properties:
source:
type: string
enum:
- mime
- extension
value:
type: string
format:
anyOf:
- type: string
- type: 'null'
description: Format kind the engine maps the claim to, or null.
truncation:
type: string
enum:
- complete
- truncated
- not-evaluated
description: 'Rule ids: magic.mismatch, magic.html-disguised, magic.no-signature, magic.binary-as-text, magic.truncated, magic.empty, magic.claims-disagree, magic.container-subtype, plus per-format png.*, jpeg.*, pdf.*, zip.*, gzip.*, webp.*, elf.*, pe.*, mp4.*.'
firstBytesHex:
type: string
bytesChecked:
type: integer
notes:
type: array
items:
type: string
description: Non-failing observations.
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:
- Magic Bytes
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