@sbo3l/sdk

Official TypeScript SDK for SBO3L — the cryptographically verifiable trust layer for autonomous AI agents.

Don't give your agent a wallet. Give it a mandate.

⚠ Status — DRAFT (F-9): package metadata, public API, and v2 capsule support are scaffolded against the v1 schemas. Final shape is gated on F-1 (auth middleware) and F-6 (capsule v2 schema) merging to main. Do not publish to npm until both land. Tracked in docs/win-backlog/05-phase-1.md.

What it does

• POST /v1/payment-requests wrapped as a typed submit() method.
• Bearer + JWT auth helpers that match the F-1 daemon contract.
• Client-side structural verifier for Passport capsules (v1 + v2). The cryptographic checks (Ed25519 signature, JCS request-hash recompute, policy-hash recompute, audit-chain walk) live in the Rust CLI sbo3l-cli passport verify --strict — this SDK does the structural and cross-field checks so callers can fail fast in JS before round-tripping.
• No fetch polyfill. Uses the runtime-provided fetch (Node ≥ 18, modern browsers). Pass an alternate via the fetch option on Node < 18.

Install

npm install @sbo3l/sdk

Quick start

import { SBO3LClient } from "@sbo3l/sdk";

const client = new SBO3LClient({
  endpoint: "http://localhost:8730",
  auth: { kind: "bearer", token: process.env.SBO3L_BEARER_TOKEN! },
});

const response = await client.submit({
  agent_id: "research-agent-01",
  task_id: "demo-task-1",
  intent: "purchase_api_call",
  amount: { value: "0.05", currency: "USD" },
  token: "USDC",
  destination: {
    type: "x402_endpoint",
    url: "https://api.example.com/v1/inference",
    method: "POST",
  },
  payment_protocol: "x402",
  chain: "base",
  provider_url: "https://api.example.com",
  expiry: "2026-05-01T10:31:00Z",
  nonce: "01HTAWX5K3R8YV9NQB7C6P2DGM",
  risk_class: "low",
});

if (response.decision === "allow") {
  console.log("execution_ref:", response.receipt.execution_ref);
}

Idempotency-safe retry

import { randomBytes } from "node:crypto";

const idempotencyKey = randomBytes(20).toString("hex"); // 40 ASCII chars

await client.submit(aprp, { idempotencyKey }); // first call
await client.submit(aprp, { idempotencyKey }); // returns cached envelope; no side effects

A retry with the same key + same canonical body returns the cached envelope. Same key + different body → HTTP 409 protocol.idempotency_conflict.

JWT (per-agent) auth

import { SBO3LClient, assertJwtSubMatches } from "@sbo3l/sdk";

const jwt = await mySigner.signJwt({ sub: "research-agent-01", iat: now() });
assertJwtSubMatches(jwt, "research-agent-01"); // local sanity check

const client = new SBO3LClient({
  endpoint: "http://localhost:8730",
  auth: { kind: "jwt", token: jwt },
});

The SDK never holds private keys. The agent ID match is enforced server-side (F-1). The client-side assertJwtSubMatches is a fail-fast convenience.

For per-request rotation, pass a supplier:

auth: { kind: "jwt-supplier", supplier: () => mySigner.signFreshJwt() }

Verifying a capsule client-side

import { verify, isCapsuleV2 } from "@sbo3l/sdk";

const capsule = JSON.parse(await fetch(capsuleUrl).then((r) => r.text()));
const result = verify(capsule);

if (!result.ok) {
  console.error("structural verification failed:");
  for (const f of result.failures) {
    console.error(`  [${f.code}] ${f.description}: ${f.detail ?? ""}`);
  }
  process.exit(2);
}

if (isCapsuleV2(capsule)) {
  // v2 capsules carry policy_snapshot + audit_segment for offline strict
  // verification by the Rust CLI.
}

The structural verifier checks:

1. schema is a known SBO3L capsule id (v1 or v2).
2. request.request_hash matches decision.receipt.request_hash.
3. policy.policy_hash matches decision.receipt.policy_hash.
4. decision.result matches decision.receipt.decision.
5. audit.audit_event_id matches decision.receipt.audit_event_id.
6. Hash + signature shapes (lowercase hex, fixed lengths).
7. Deny capsules must have execution.status === "not_called".
8. Live-mode capsules must carry non-empty live_evidence.
9. Mock-mode capsules must not carry live_evidence.
10. Embedded checkpoint (when present) is mock_anchor: true with a local-mock-anchor-<16hex> ref.

For full crypto verification (Ed25519 receipt signature, JCS request-hash recompute, policy-hash recompute, audit-chain walk), use the Rust CLI:

sbo3l-cli passport verify --strict --path capsule.json

Errors

| Class | When | |---|---| | SBO3LError | Daemon returned a non-2xx response. Carries the RFC 7807 problem-detail body verbatim; .code and .status are first-class. | | SBO3LTransportError | Network failure, timeout, or unparseable 200 body. | | PassportVerificationError | Thrown by verifyOrThrow(). Carries .codes (array of failure codes). |

import { SBO3LError } from "@sbo3l/sdk";

try {
  await client.submit(aprp);
} catch (err) {
  if (err instanceof SBO3LError && err.code === "auth.required") {
    // re-acquire token
  } else {
    throw err;
  }
}

API reference

Full type-checked API surface; every export has JSDoc. Generate locally with:

npm run typecheck

Public exports:

• SBO3LClient — top-level client (submit, health, passport)
• verify, verifyOrThrow — capsule structural verifier
• authHeader, decodeJwtClaims, assertJwtSubMatches — auth helpers
• SBO3LError, SBO3LTransportError, PassportVerificationError, isProblemDetail — error types
• isCapsuleV1, isCapsuleV2 — capsule discriminators
• All wire types: PaymentRequest, PolicyReceipt, PassportCapsule, etc.
• VERSION — package version string

Compatibility

• Node: ≥ 18 (for global fetch and AbortController).
• Browsers: modern (Chrome ≥ 88, Firefox ≥ 90, Safari ≥ 14).
• Daemon: SBO3L server 0.1.0+ (matches sbo3l-server workspace version).

Development

npm install
npm run typecheck
npm test
npm run build
gzip -c dist/index.js | wc -c   # bundle size check (must be < 50000)

License

MIT — see LICENSE at the repo root.