Strands Agents

agent402-strands · npm · MIT

Strands tool({...}) instances for TypeScript agents, including Strands agents running on AWS Bedrock AgentCore. Pull a curated subset of the catalog into the agent; when it calls a tool, the adapter solves a proof-of-work or signs an x402 payment and returns the structured result.

Install

npm install agent402-strands @strands-agents/sdk zod @x402/fetch @x402/core @x402/evm viem

Example

import { Agent } from "@strands-agents/sdk";
import { agent402Tools } from "agent402-strands";
import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const payClient = new x402Client();
registerExactEvmScheme(payClient, { signer: privateKeyToAccount(process.env.AGENT_KEY) });
const payFetch = wrapFetchWithPayment(fetch, payClient);

// web search, then a cited answer: both paid per call from the wallet
const { tools } = await agent402Tools({
  slugs: ["search", "answer"],
  freeOnly: false,
  fetch: payFetch,
});

const agent = new Agent({ tools });
const out = await agent.invoke("Search the web for x402 payment protocol adoption, then answer with citations: what is the x402 payment protocol?");

No wallet yet? The pure-CPU tools (hash, uuid, base64, markdown, JSON and more) run free with proof-of-work and no wallet:

// free tier: every tool listed here is compute-payable (proof-of-work, no wallet)
const { tools } = await agent402Tools({
  slugs: ["hash", "markdown-to-html", "text-stats", "uuid"],
});

What it exposes

One native tool per catalog slug you pass in slugs (a short list gives the model better tool selection).
With no slugs, the free-tier catalog: every compute-payable tool (freeOnly: true is the default).
An execute(name, args) function that runs a tool call and pays for it underneath.
baseUrl points the adapter at a self-hosted Agent402 instance.
A client field with the underlying buyer SDK (find(), call(), clearCache()), and agent402Execute() for a standalone executor.

How payment works

Free tier: compute-payable tools settle with a sha256 proof-of-work solved in-process. No wallet, no API key.
Wallet-only tools (browser, network, memory, live data): set freeOnly: false and pass a payment-wrapped fetch. An @x402/fetch fetch pays in USDC over x402; a stock mppx fetch pays over MPP. The same 402 carries both offers.
Prices come from the live catalog at /api/pricing and are quoted in every 402 before anything is signed.

A paid call that ends in any status of 400 or above is not charged over x402: settlement runs after the tool and only on a successful response. Background: What x402 is · MPP (Machine Payments Protocol).

Configuration

Option	Type	Description
`slugs`	`string[]`	Load only these tools (a short list gives the model better tool selection).
`freeOnly`	`boolean`	Default true: keep only compute-payable tools, paid with proof-of-work. Set false to include wallet-only tools.
`fetch`	`typeof fetch`	A payment-wrapped fetch (@x402/fetch for x402, mppx for MPP) that pays wallet-only tools.
`baseUrl`	`string`	Point to a self-hosted Agent402 instance.

// Load only these tools (a short list gives the model better tool selection).
agent402Tools({ slugs: ["hash", "markdown-to-html"] })

// Default true: keep only compute-payable tools, paid with proof-of-work. Set false to include wallet-only tools.
agent402Tools({ slugs: ["extract", "hash"], freeOnly: false, fetch: payFetch })

// A payment-wrapped fetch (@x402/fetch for x402, mppx for MPP) that pays wallet-only tools.
agent402Tools({ freeOnly: false, fetch: payFetch })

// Point to a self-hosted Agent402 instance.
agent402Tools({ baseUrl: "https://my-agent402.example.com" })

works with@strands-agents/sdkAWS Bedrock AgentCoreAny Strands-compatible model