eino-acp

Eino ChatModel provider that connects to any ACP (Agent Client Protocol) compatible coding agent.

Use Claude Code, Codex CLI, Gemini CLI, or any other ACP agent as an LLM backend for CloudWeGo Eino.

Install

go get github.com/strrl/eino-acp

Usage

package main

import (
	"context"
	"fmt"

	einoacp "github.com/strrl/eino-acp"
)

func main() {
	ctx := context.Background()

	cm, err := einoacp.NewChatModel(ctx, &einoacp.Config{
		Command: einoacp.ClaudeCommand(),
		// or: einoacp.CodexCommand()
		// or: einoacp.GeminiCommand()
	})
	if err != nil {
		panic(err)
	}

	// Generate (non-streaming)
	msg, err := cm.Generate(ctx, einoacp.UserMessages("Hello!"))
	if err != nil {
		panic(err)
	}
	fmt.Println(msg.Content)

	// Stream
	stream, err := cm.Stream(ctx, einoacp.UserMessages("Tell me a joke."))
	if err != nil {
		panic(err)
	}
	defer stream.Close()

	for {
		chunk, err := stream.Recv()
		if err != nil {
			break
		}
		fmt.Print(chunk.Content)
	}
	fmt.Println()
}

Config

Field	Description
Command	Command to launch the ACP agent. Use ClaudeCommand(), CodexCommand(), or GeminiCommand() helpers, which auto-detect bunx, then pnpm dlx, then npx -y. Required.
Cwd	Working directory for the agent session. Defaults to current directory.
Env	Additional environment variables for the agent subprocess.
AutoApprove	Auto-approve all permission requests from the agent. Default false.

How it works

1. Launches the agent as a subprocess
2. Communicates via ACP (JSON-RPC 2.0 over stdio)
3. Maps ACP session updates to Eino's schema.Message streaming interface

Tool Call Mapping

eino-acp translates ACP tool_call and tool_call_update session updates into Eino assistant ToolCalls.

ACP field	Eino field	Notes
toolCallId	ToolCall.ID	Preserved as-is.
kind	ToolCall.Function.Name	Uses ACP tool kind such as read, edit, or execute. Falls back to other when ACP omits the kind.
rawInput	ToolCall.Function.Arguments	JSON-marshaled into a stable string. Defaults to {} when missing.
title, status, rawOutput, locations, content, _meta	ToolCall.Extra	Preserved under acp_* keys so observability consumers can inspect ACP-specific metadata.

For Generate, the final assistant message includes the accumulated ToolCalls.

For Stream, each ACP tool event is emitted as an assistant chunk with empty Content and a single ToolCall, so consumers such as tape, Langfuse-style handlers, or ADK can observe tool activity as it happens.

agent_thought_chunk, plan, and other non-message ACP session updates are still ignored.

Built on coder/acp-go-sdk.

License

MIT