@proof-meter/sdk

Cryptographic billing attestation for AI systems. Every LLM call, API hit, and autonomous action gets a signed, tamper-evident receipt.

This is the branded SDK for Proof Meter. It wraps the open-source @verifiedstate/sdk with Proof Meter defaults and a branded ProofMeter client class.

Install

npm install @proof-meter/sdk

Quick Start

import { ProofMeter } from '@proof-meter/sdk';

const meter = new ProofMeter({ apiKey: 'pm_...' });

// After any billable event
const receipt = await meter.spend({
  provider: 'openai',
  model: 'gpt-4o',
  tokens: 2560,
  cost: 4.2,
});

console.log(receipt.receipt_id); // rcpt_7f3a...
console.log(receipt.status);     // 'signed'

What you get

• Ed25519 signed receipts for every billable event
• Merkle chain — tamper-evident append-only log
• SCITT-compatible envelope format (COSE_Sign1)
• Public verification — anyone can verify any receipt

Full API

The ProofMeter class extends VerifiedStateClient with all its methods:

• meter.spend(params) — record a billable event, get a receipt
• meter.sign(params) — alias for spend
• meter.query(params) — search your receipts and assertions
• meter.receipt(id) — get a specific receipt with evidence
• meter.verify(params) — run verification ladder
• meter.health(namespaceId) — namespace health metrics

Links

• proofmeter.com — product homepage
• verifiedstate.ai — open-source substrate
• Docs — API documentation (coming soon)

License

Apache-2.0