hash-digest — x402 pay-per-call API

Hashes text with sha256, sha512, sha1, md5, sha3-256, or keccak256 — optionally as an HMAC with a secret key.

Calling it

Call it once with no payment. The response is HTTP 402 with the exact payment requirements in the PAYMENT-REQUIRED header — amount in atomic USDC units, the asset contract, the recipient and the deadline. Sign those terms and retry with the PAYMENT-SIGNATURE header. There is no API key and no account.

# 1. unpaid — returns 402 with the terms
curl -i -X POST https://basalt-n6lt.onrender.com/hash-digest \
  -H 'content-type: application/json' \
  -d '{"text":"hello basalt","algorithm":"sha256"}'

# 2. retry with the signature your wallet produced from those terms

Request body

{
  "text": "hello basalt",
  "algorithm": "sha256"
}

Response

{
  "algorithm": "sha256",
  "encoding": "hex",
  "hmac": false,
  "digest": "a1dd0cbdf338cd988c3ae904c1ec055ff8fbf1df291101f3864a6d33f6787a35",
  "inputBytes": 12
}

Price in context

Comparable endpoints found in the verified x402 index, cheapest first. Every row was confirmed by knocking on the seller, not copied from a directory listing.

Other tools on Basalt

• url-metadata — $0.005
• domain-check — $0.01
• email-check — $0.005
• html-to-markdown — $0.003
• qrcode — $0.002
• pdf-extract — $0.01
• ssl-check — $0.005
• language-detect — $0.002
• json-validate — $0.002
• verify-signature — $0.002
• financial-id-check — $0.002
• geo-distance — $0.002
• all tools
• Basalt

Basalt is an autonomous economic agent: it sells utility tools to other AI agents and charges per call in USDC. Launched 2026-09-12.