JavaScript / TypeScript SDK

npm install @kya/sdk-js
# or
pnpm add @kya/sdk-js

import { generateKeypair } from "@kya/sdk-js";

const { publicKey, privateKey } = await generateKeypair();
// publicKey: base64-encoded Ed25519 public key
// privateKey: base64-encoded Ed25519 private key

console.log("Public key:", publicKey);
// Store privateKey securely — never expose it

import { canonicalize, hashPayload, signPayload } from "@kya/sdk-js";

const payload = {
  action: "charge_payment",
  amount: 45,
  currency: "EUR",
  agent_id: "agt_01J...",
};

// 1. Canonical JSON (deterministic key ordering)
const canonical = canonicalize(payload);

// 2. SHA-256 hash
const payloadHash = hashPayload(canonical);

// 3. Ed25519 signature
const signature = await signPayload(canonical, privateKey);

console.log({ payloadHash, signature });

import { KyaClient, generateKeypair, signPayload, hashPayload, canonicalize } from "@kya/sdk-js";

const kya = new KyaClient({
  baseUrl: "https://api.know-your-agent.dev",
  workspaceId: "ws_01J...",
});

// 1. Request a capability token
const { capability_token } = await kya.requestCapability({
  agentId: "agt_01J...",
  action: "charge_payment",
  ttlSeconds: 300,
});

// 2. Sign the action payload
const payload = { action: "charge_payment", amount: 45 };
const canonical = canonicalize(payload);
const payloadHash = hashPayload(canonical);
const signature = await signPayload(canonical, agentPrivateKey);

// 3. Call verify
const { decision, reason_code, audit_event_id } = await kya.verify({
  agentId: "agt_01J...",
  capabilityToken: capability_token,
  action: "charge_payment",
  payload,
  signature,
  payloadHash,
});

if (decision === "ALLOW") {
  // Execute the action
  await processPayment(45);
} else {
  console.error("Action denied:", reason_code);
}

import express from "express";
import { KyaClient } from "@kya/sdk-js";

const kya = new KyaClient({ baseUrl: "...", workspaceId: "ws_01J..." });

// Protect a route with KYA verification
app.post("/charge", async (req, res) => {
  const { capability_token, signature, payload_hash, ...payload } = req.body;

  const result = await kya.verify({
    agentId: req.headers["x-agent-id"] as string,
    capabilityToken: capability_token,
    action: "charge_payment",
    payload,
    signature,
    payloadHash: payload_hash,
  });

  if (result.decision !== "ALLOW") {
    return res.status(403).json({
      error: result.reason_code,
      audit_event_id: result.audit_event_id,
    });
  }

  // Proceed with the action
  res.json({ success: true });
});