# Agent Rail API

Pay-per-call data endpoints for AI agents: multi-chain reads (Base, Ethereum, Arbitrum, Polygon)
and Nigerian reference data. No signup, no account, no API key.
Two ways to pay for the same endpoints:

 1. USDC over x402 (Base or Polygon). An unpaid call returns HTTP 402 with machine-readable
    terms; retry with an x402 payment header. The payer needs no gas — the facilitator pays it.
 2. Naira credit packs via Paystack. Buy a pack, receive an API key, send it as the X-API-Key
    header. Intended for Nigerian businesses that settle in naira.

## Paid endpoints (either rail)
- GET https://api.postandshare.net/v1/ng/phone/lookup — $0.003 — Validate a Nigerian phone number: carrier, line type, E.164 normalisation
- GET https://api.postandshare.net/v1/ng/bank/validate — $0.003 — Validate a Nigerian NUBAN account number against its bank code
- GET https://api.postandshare.net/v1/ng/identity/format — $0.002 — Format-validate a Nigerian NIN / BVN / TIN / CAC number (no data lookup)
- GET https://api.postandshare.net/v1/chain/block-number — $0.001 — Current block number on Base, Ethereum, Arbitrum or Polygon
- GET https://api.postandshare.net/v1/chain/balance — $0.001 — Native-token balance of an EVM address, with a USD value
- GET https://api.postandshare.net/v1/chain/gas — $0.001 — Current gas price plus the cost of a plain native transfer, in token and USD
- GET https://api.postandshare.net/v1/chain/block — $0.001 — Block header by number or latest: timestamp, tx count, gas used, base fee
- GET https://api.postandshare.net/v1/chain/tx — $0.001 — Transaction receipt by hash: status, block, gas used, fee in token and USD
- GET https://api.postandshare.net/v1/chain/token — $0.001 — ERC-20 token metadata and a holder balance (symbol, name, decimals, amount)

## Free endpoints
- POST https://api.postandshare.net/mcp — remote MCP server (streamable HTTP). tools/list is free; the paid
  tools return the live payment challenge rather than data.
- GET https://api.postandshare.net/v1/chain/networks — supported chains, chain ids and native tokens
- GET https://api.postandshare.net/v1/ng/states — list Nigerian states and capitals
- GET https://api.postandshare.net/openapi.json — OpenAPI description
- GET https://api.postandshare.net/billing/packs — naira credit packs and prices
- GET https://api.postandshare.net/health

Format/reference validation only: no personal data is returned and no identity database is queried.