dart_acp

dart_acp is a collection of Dart packages for the Agent Client Protocol (ACP). It includes the typed protocol SDK and ready-to-use clients for OpenCode, Gemini CLI, Claude Code, and Codex.

Every provider package exposes the same client shape: an asynchronous <Provider>AcpClient.start() constructor, connection and agent accessors, a closed future, idempotent close(), and a matching <Provider>AcpClientOptions configuration type.

Claude, Codex, and Antigravity also expose their lower-level adapter APIs for custom transports and service boundaries.

Choose a provider package for the quickest path to an agent:

dart pub add dart_acp_opencode

import 'dart:io';

import 'package:dart_acp_opencode/dart_acp_opencode.dart';

Future<void> main() async {
  final client = await OpenCodeAcpClient.start();
  try {
    final session = await client.agent
        .newSession(cwd: AcpAbsolutePath(Directory.current.path))
        .start();
    // Prompt through session.prompt(...), then consume the streamed result.
    session.dispose();
  } finally {
    await client.close();
  }
}

The equivalent entry points are GeminiAcpClient.start(), ClaudeAcpClient.start(), CodexAcpClient.start(), and AntigravityAcpClient.start().

Use dart_acp_sdk directly when implementing an ACP client, agent, transport, or remote protocol host. Its default library is the stable ACP v1 surface. Draft v2, unstable protocol overlays, HTTP/SSE, WebSocket, and server APIs use explicit experimental imports.

The smallest complete SDK example builds an in-memory client and agent, negotiates ACP v1, opens a session, streams an agent message, and closes both ends:

dart run packages/dart_acp_sdk/example/quick_start.dart

Output:

Hello from Dart ACP.

See the package README for the complete walkthrough, supported method matrix, version boundaries, and transport guidance.

This repository is a Melos workspace:

packages/
├── claude_agent_sdk/
├── dart_acp_antigravity/
├── dart_acp_claude/
├── dart_acp_codex/
├── dart_acp_gemini/
├── dart_acp_opencode/
└── dart_acp_sdk/

Common workspace verification commands:

dart run melos bootstrap
dart run melos run format
dart run melos run analyze
dart run melos run test
dart run melos run publish:dry-run

The core SDK additionally has deterministic schema, browser, coverage, example, and benchmark gates. See its package README and contribution guide for the complete command set.

SDK code generation uses the schema snapshots committed under packages/dart_acp_sdk/tool/schema/snapshots/. Refreshing those snapshots is an explicit operation:

dart run melos run schema:sync

• SDK examples
• SDK benchmarks
• Security guidance
• Contributing
• SDK changelog

Measured on 2026-07-29 with Dart 3.12.2 on arm64 macOS:

Licensed under the Apache License 2.0.