@arcturn/tools

The built-in tool set for the Arcturn agent harness: read, write, edit, bash, grep, glob, ls, fetch, and websearch. Each tool implements the Tool interface from @arcturn/types, so they compose with any custom tools you add.

What's in it

src/index.ts exports:

• createDefaultTools(options) — the one-call entry point. Returns { tools, read, write, edit, bash, grep, glob, ... }: the full array plus each tool individually.
• Individual factories: createReadTool, createWriteTool, createEditTool, createBashTool, createGrepTool, createGlobTool, createLsTool, createFetchTool, createWebSearchTool.
• BackgroundTaskManager — tracks long-running background bash processes.
• Sandbox helpers for the bash tool: resolveSandboxInvocation, buildSandboxExecProfile (macOS sandbox-exec), buildBwrapArgv (Linux bubblewrap), defaultSandboxProbe.
• resolvePath — the shared cwd-relative path resolution every tool uses.

Every tool resolves relative paths against ToolExecutionContext.cwd at execution time, not at construction time.

Install

Arcturn is not yet published to npm. Until it is, use it from a clone of the monorepo as a pnpm workspace package:

git clone https://github.com/sitharaj88/arcturn.git && cd arcturn
pnpm install && pnpm -r build

Then depend on it from another workspace package: "@arcturn/tools": "workspace:*".

Usage

import { createDefaultTools } from "@arcturn/tools";
import { createAgent } from "@arcturn/core";
import { createClient, requireModel } from "@arcturn/ai";

const llm = createClient();
const { tools } = createDefaultTools({ cwd: process.cwd() });

const agent = createAgent({
  llm,
  model: requireModel("anthropic/claude-sonnet-4-5"),
  systemPrompt: "You are a focused, careful coding agent.",
  tools,
  cwd: process.cwd(),
});

Mix in your own tools or MCP-bridged tools freely — the model sees no difference: createAgent({ llm, model, tools: [...tools, ...myCustomTools], cwd }).

Docs

• Custom tools — the Tool interface, a worked example, and how permissions gate execute.
• Embedding with the SDK — how this fits with @arcturn/core.

License

Apache-2.0 — see LICENSE.

👤 Author

Sitharaj Seenivasan

• 🌐 Website: sitharaj.in
• 💼 LinkedIn: sitharaj08
• 💻 GitHub: sitharaj88

☕ Support

If this project helps you, consider buying me a coffee — it keeps the work going.

📄 License

Licensed under the Apache License 2.0. © 2026 Sitharaj Seenivasan.