# Use ACP-compatible harnesses with the AI SDK harness layer

Source: [Vercel](https://vercel.com/changelog/use-acp-compatible-harnesses-with-the-ai-sdk-harness-layer)  
Feed7 permalink: https://feed7.dev/p/use-acp-compatible-harnesses-with-the-ai-sdk-harness-lay-a44214149b  
Published: 2026-08-13T00:00:00.000Z  
Trust: Official Source (official_source)

## Why Included

Use ACP for portable harness integration, but test permissions, events, and runtime-specific controls before replacing a direct adapter.

## Source Summary

A new ACP meta-adapter lets HarnessAgent run compatible runtimes that lack dedicated integrations. Keep direct Claude Code and Codex adapters where tighter behavior matters.

## Practical Implication

Use the meta-adapter to connect a compatible harness that has no native AI SDK integration. For Claude Code and Codex, Vercel recommends their dedicated adapters because they can expose runtime behavior more precisely.

## Agent-Ready Context

The new **@ai-sdk/harness-acp** package adapts the Agent Client Protocol rather than one runtime. Builders pass an ACP-compatible package to **createACP**, map the harness basics, and use the result with HarnessAgent.

Use the meta-adapter to connect a compatible harness that has no native AI SDK integration. For **Claude Code and Codex**, Vercel recommends their dedicated adapters because they can expose runtime behavior more precisely.

ACP is not universal, and its abstraction may limit or alter access to a harness’s internals. Treat protocol compatibility as a portability option, then test permissions, events, and runtime-specific behavior before replacing a direct adapter.

## Context Map

- Layer: tools
- Domains: coding
- Topics: coding-agents, agent-sdks, harness-engineering

## Uncertainty

- None recorded.

## Agent Instruction

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