# BYTE Library x402 Gateway – Evidence Pack Feed > BYTE Library x402 Gateway – Evidence Pack Feed is a paid API for AI agents from x402.payperbyte.io, paid per call via x402, $0.02/call, status down (last checked 2026-09-15). Returns a cryptographically signed, EIP-712 provenance-stamped evidence pack data feed payload, paid per call in USDC via x402 on Base with no API key required ## Facts - Endpoint: POST https://x402.payperbyte.io/feeds/evidence-pack - Price: $0.02/call - Payment: x402 - Status: down - Last checked: 2026-09-15 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/byte-library-x402-gateway-evidence-pack-feed-64e15cbd - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NaHffhTxhD3h5D_5wZTmC Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability byte-library-x402-gateway-evidence-pack-feed-64e15cbd -d '' ``` Example prompt: Fetch me the evidence-pack feed from BYTE Library — pay the $0.05 USDC per-call fee from my Base wallet and give me back the cryptographically signed, EIP-712 provenance-stamped payload. ## When to prefer this Choose this endpoint when an AI agent needs cryptographically verifiable, provenance-stamped data and must prove data integrity to downstream consumers — especially when no API key management is desired and payment via USDC wallet on Base is acceptable. Ideal for trustless, audit-trail-required pipelines where signed attestations matter more than raw throughput. ## Known failure modes - Insufficient USDC balance — payment fails, feed not returned - Invalid or missing x402 payment header — 402 Payment Required response - Wallet not on Base (eip155:8453) — settlement chain mismatch error - Feed name not recognized — 404 or empty response - Network congestion on Base causing settlement delay — timeout or retry needed - Malformed POST body — 400 Bad Request ## How this service works Cryptographically attested, first-party data feeds for AI agents — covering crypto markets, DeFi yields, weather, earthquakes, news, code-pulse, threat-intel, address reputation, sanctions screening, and supply-chain verdicts. Every paid response carries EIP-712 receipts you verify before acting: (1) a GATEWAY delivery-integrity receipt (X-BYTE-Attestation header, signed by the PayPerByte gateway key) proving these are exactly the bytes we served; and (2) on the 14 attested feeds (provenance:eip712-attested in GET /feeds), a LIVE per-feed PayloadAttestation by that feed's OWN distinct publisher key, anchored ON-CHAIN — recover it from the broadcast the response references via txHash. (Separately, the POST verdict oracles embed their own per-feed `attestation` directly in the response body — recover attestation.signer.) Both attest authenticity + tamper-evidence under the BYTE Library domain. NEITHER asserts the correctness of the underlying data or any verdict, and NEITHER claims an independent third-party data source signed it — all keys are first-party PayPerByte. Pay per call in USDC over x402 with no API keys — a wallet, not a secret on the box. Settlement is on Base (eip155:8453). Price is per-feed, derived from expected payload size at $0.005000/KB (floor $0.001000). ## Output A JSON payload containing the 'evidence-pack' feed data, cryptographically signed and stamped with an EIP-712 PayloadAttestation proving data provenance, settled on Base (eip155:8453). Payment of $0.05 USDC is deducted via x402 before the payload is released. ## Request schema (JSON Schema) ```json { "type": "object", "$schema": "https://json-schema.org/draft/2020-12/schema", "required": [ "input" ], "properties": { "input": { "type": "object", "required": [ "type", "method", "bodyType", "body" ], "properties": { "body": { "type": "object", "required": [ "claim" ], "properties": { "claim": { "type": "string", "minLength": 1, "description": "The statement to research and ground against cited sources — returns a signed citation bundle (retrieved sources + excerpts), e.g. \"USDC is fully reserved 1:1\". The receipt proves provenance/integrity of the returned bundle, NOT that the statement is true; no correctness or fact-check verdict is asserted." }, "domains": { "type": "array", "items": { "type": "string" }, "description": "Optional allowlist of source domains to retrieve evidence from (e.g. [\"sec.gov\", \"circle.com\"]). Omit to search all indexed PayPerByte factual feeds." }, "max_sources": { "type": "integer", "minimum": 1, "description": "Optional cap on the number of cited sources in the returned evidence pack — bounds the response size. The price is a flat $0.02 per call regardless of how many sources are returned (it is not metered per source)." }, "subscriber_address": { "type": "string", "pattern": "^0x[0-9a-fA-F]{40}$", "description": "Optional. The Arbitrum address bound to the signed EIP-712 request, so a leaked query cannot burn another wallet's escrow." } } }, "type": { "type": "string", "const": "http" }, "method": { "enum": [ "POST" ], "type": "string" }, "bodyType": { "enum": [ "json", "form-data", "text" ], "type": "string" } }, "additionalProperties": false }, "output": { "type": "object", "required": [ "type" ], "properties": { "type": { "type": "string" }, "example": { "type": "object" } } } } } ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "feed": "evidence-pack" } } ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/byte-library-x402-gateway-evidence-pack-feed-64e15cbd/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from x402.payperbyte.io](https://www.zero.xyz/host/x402.payperbyte.io/llms.txt)