generated: '2026-09-19'
method: searched
source: https://coinrailz.com/.well-known/agent-instructions.json + https://coinrailz.com/api/auth/capabilities
  + live 402 body from POST https://coinrailz.com/x402/ping
description: 'Coin Railz publishes no separate sandbox environment, test network or test-mode key prefix: every
  key is cr_live_ and every service runs against mainnet data. What it publishes instead is a free-trial path and
  a free, unpaid 402 rehearsal, recorded here verbatim. Nothing below is a test value invented by us.'
environments:
- name: production
  base_url: https://coinrailz.com
  note: Only environment. Payment networks are mainnets (Base eip155:8453, Arc eip155:5042, Ethereum, Arbitrum,
    Solana mainnet).
key_prefixes:
- prefix: cr_live_
  mode: live
  note: The only documented prefix; trial keys share it.
free_trial:
  endpoint: GET https://coinrailz.com/api/m2m/credits/trial
  operationId: getTrialKey
  credits_usd: 5
  approx_calls: 80-100
  expires: 7 days
  limit: 1 per IP per 7 days
  returned_once: true
  note: '"SAVE the key - it is not stored in plaintext and cannot be retrieved again." (402 body). Not exercised
    by this pass: calling it provisions a real key.'
first_call_free:
  services:
  - gas-price-oracle
  - token-metadata
  note: '"FREE for first-time users" per the stdio MCP README and the extended agent card (standard per-IP/UA eligibility).'
unpaid_rehearsal:
  endpoint: POST https://coinrailz.com/x402/ping
  operationId: ping
  observed_status: 402
  note: Without payment the endpoint returns the full x402 challenge (PAYMENT-REQUIRED header, accepts[] entries
    for Base, Arc and Solana) so a client can test challenge parsing and EIP-712 signing before spending; the paid
    ping costs $0.25 USDC.
test_values: []
test_clocks: null
x-caveat: No sandbox pointer is emitted as a Console/Playground claim beyond the free-trial path; the provider itself
  calls this a trial, not a sandbox.