---
title: "ACP"
description: "ACP skill for Vellum — delegates development tasks through the Agent Client Protocol."
canonical_url: "https://www.vellum.ai/docs/skills-reference/acp"
md_url: "https://www.vellum.ai/md/docs/skills-reference/acp"
related:
  - "/docs/skills-reference"
  - "/docs/skills-reference/amazon"
  - "/docs/skills-reference/app-builder"
  - "/docs/skills-reference/browser"
  - "/docs/skills-reference/chatgpt-import"
  - "/docs/skills-reference/computer-use"
  - "/docs/skills-reference/contacts"
  - "/docs/skills-reference/document"
---

# ACP

## What it does

Lets your assistant delegate development tasks to external tools such as Claude Code, Codex, and Gemini CLI through the Agent Client Protocol.

## Setup required

Requires the external agent to be installed (e.g., Claude Code CLI). Say “Set up ACP” for first-time configuration.

## Permissions

- Host shell access for spawning external processes

## Common prompts

| You say...                                    | What happens                   |
| --------------------------------------------- | ------------------------------ |
| “Use Claude Code to fix the bug in server.ts” | Delegates to Claude Code agent |
| “Ask Codex to refactor this module”           | Delegates to Codex             |
| “Check on my coding agent”                    | Gets agent status              |
| “Cancel the coding agent”                     | Aborts the agent               |

## Configuration

- Supports multiple external development tools (Claude Code, Codex, Gemini CLI)
- Agents run as separate processes with their own context
- Status tracking: pending, running, completed, failed, aborted

## Tips & gotchas

- **Fully independent.** ACP agents are separate processes with their own context window and tools.
- **Self-contained tasks.** Best for tasks like fixing a bug, refactoring a file, or writing tests.
- **Coordinated results.** Your assistant coordinates with the agent and reports back results.
- **Choose the right agent.** Claude Code for general development, Codex for code generation, Gemini CLI for Google ecosystem integration.