Simple blocking prompt

import { createAgent } from "@codeany/open-agent-sdk";

const agent = createAgent({ model: "claude-sonnet-4-6" });
const result = await agent.prompt("What files are in this project?");

console.log(result.text);
console.log(
  `Turns: ${result.num_turns}, Tokens: ${result.usage.input_tokens + result.usage.output_tokens}`,
);

OpenAI / GPT models

import { createAgent } from "@codeany/open-agent-sdk";

const agent = createAgent({
  apiType: "openai-completions",
  model: "gpt-4o",
  apiKey: "sk-...",
  baseURL: "https://api.openai.com/v1",
});

const result = await agent.prompt("What files are in this project?");
console.log(result.text);

The apiType is auto-detected from model name — models containing gpt-, o1, o3, deepseek, qwen, mistral, etc. automatically use openai-completions.

Multi-turn conversation

import { createAgent } from "@codeany/open-agent-sdk";

const agent = createAgent({ maxTurns: 5 });

const r1 = await agent.prompt(
  'Create a file /tmp/hello.txt with "Hello World"',
);
console.log(r1.text);

const r2 = await agent.prompt("Read back the file you just created");
console.log(r2.text);

console.log(`Session messages: ${agent.getMessages().length}`);

Custom tools (Zod schema)

import { z } from "zod";
import { query, tool, createSdkMcpServer } from "@codeany/open-agent-sdk";

const getWeather = tool(
  "get_weather",
  "Get the temperature for a city",
  { city: z.string().describe("City name") },
  async ({ city }) => ({
    content: [{ type: "text", text: `${city}: 22°C, sunny` }],
  }),
);

const server = createSdkMcpServer({ name: "weather", tools: [getWeather] });

for await (const msg of query({
  prompt: "What is the weather in Tokyo?",
  options: { mcpServers: { weather: server } },
})) {
  if (msg.type === "result")
    console.log(`Done: $${msg.total_cost_usd?.toFixed(4)}`);
}

Custom tools (low-level)

import {
  createAgent,
  getAllBaseTools,
  defineTool,
} from "@codeany/open-agent-sdk";

const calculator = defineTool({
  name: "Calculator",
  description: "Evaluate a math expression",
  inputSchema: {
    type: "object",
    properties: { expression: { type: "string" } },
    required: ["expression"],
  },
  isReadOnly: true,
  async call(input) {
    const result = Function(`'use strict'; return (${input.expression})`)();
    return `${input.expression} = ${result}`;
  },
});

const agent = createAgent({ tools: [...getAllBaseTools(), calculator] });
const r = await agent.prompt("Calculate 2**10 * 3");
console.log(r.text);

Skills

Skills are reusable prompt templates that extend agent capabilities. Five bundled skills are included: simplify, commit, review, debug, test.

import {
  createAgent,
  registerSkill,
  getAllSkills,
} from "@codeany/open-agent-sdk";

// Register a custom skill
registerSkill({
  name: "explain",
  description: "Explain a concept in simple terms",
  userInvocable: true,
  async getPrompt(args) {
    return [
      {
        type: "text",
        text: `Explain in simple terms: ${args || "Ask what to explain."}`,
      },
    ];
  },
});

console.log(`${getAllSkills().length} skills registered`);

// The model can invoke skills via the Skill tool
const agent = createAgent();
const result = await agent.prompt('Use the "explain" skill to explain git rebase');
console.log(result.text);

Hooks (lifecycle events)

import { createAgent, createHookRegistry } from "@codeany/open-agent-sdk";

const hooks = createHookRegistry({
  PreToolUse: [
    {
      handler: async (input) => {
        console.log(`About to use: ${input.toolName}`);
        // Return { block: true } to prevent tool execution
      },
    },
  ],
  PostToolUse: [
    {
      handler: async (input) => {
        console.log(`Tool ${input.toolName} completed`);
      },
    },
  ],
});

20 lifecycle events: PreToolUse, PostToolUse, PostToolUseFailure, SessionStart, SessionEnd, Stop, SubagentStart, SubagentStop, UserPromptSubmit, PermissionRequest, PermissionDenied, TaskCreated, TaskCompleted, ConfigChange, CwdChanged, FileChanged, Notification, PreCompact, PostCompact, TeammateIdle.

MCP server integration

import { createAgent } from "@codeany/open-agent-sdk";

const agent = createAgent({
  mcpServers: {
    filesystem: {
      command: "npx",
      args: ["-y", "@modelcontextprotocol/server-filesystem", "/tmp"],
    },
  },
});

const result = await agent.prompt("List files in /tmp");
console.log(result.text);
await agent.close();

Subagents

import { query } from "@codeany/open-agent-sdk";

for await (const msg of query({
  prompt: "Use the code-reviewer agent to review src/index.ts",
  options: {
    agents: {
      "code-reviewer": {
        description: "Expert code reviewer",
        prompt: "Analyze code quality. Focus on security and performance.",
        tools: ["Read", "Glob", "Grep"],
      },
    },
  },
})) {
  if (msg.type === "result") console.log("Done");
}

Permissions

import { query } from "@codeany/open-agent-sdk";

// Read-only agent — can only analyze, not modify
for await (const msg of query({
  prompt: "Review the code in src/ for best practices.",
  options: {
    allowedTools: ["Read", "Glob", "Grep"],
    permissionMode: "dontAsk",
  },
})) {
  // ...
}

Web UI

A built-in web chat interface is included for testing:

npx tsx examples/web/server.ts
# Open http://localhost:8081

API reference

Top-level functions

| Function | Description | | ------------------------------------- | -------------------------------------------------------------- | | query({ prompt, options }) | One-shot streaming query, returns AsyncGenerator<SDKMessage> | | createAgent(options) | Create a reusable agent with session persistence | | tool(name, desc, schema, handler) | Create a tool with Zod schema validation | | createSdkMcpServer({ name, tools }) | Bundle tools into an in-process MCP server | | defineTool(config) | Low-level tool definition helper | | getAllBaseTools() | Get all 35+ built-in tools | | registerSkill(definition) | Register a custom skill | | getAllSkills() | Get all registered skills | | createProvider(apiType, opts) | Create an LLM provider directly | | createHookRegistry(config) | Create a hook registry for lifecycle events | | listSessions() | List persisted sessions | | forkSession(id) | Fork a session for branching |

Agent methods

| Method | Description | | ------------------------------- | ----------------------------------------------------- | | agent.query(prompt) | Streaming query, returns AsyncGenerator<SDKMessage> | | agent.prompt(text) | Blocking query, returns Promise<QueryResult> | | agent.getMessages() | Get conversation history | | agent.clear() | Reset session | | agent.interrupt() | Abort current query | | agent.setModel(model) | Change model mid-session | | agent.setPermissionMode(mode) | Change permission mode | | agent.getApiType() | Get current API type | | agent.close() | Close MCP connections, persist session |

Options

| Option | Type