Description

Problem Description：
When using the write tool to create a new file, the client (IntelliJ IDEA) hangs indefinitely in the chat interface with a "waiting" indicator. The file is actually created successfully on disk, but the client never receives a completion signal. Manually clicking the "stop" button immediately reveals the created file.

In contrast, using the edit tool to modify an existing file or the bash tool to delete a file works perfectly – the client receives proper responses and the operation completes normally.

Environment:

• OpenCode version: v1.2.15 (binary opencode-windows-x64.zip)
• Client: IntelliJ IDEA using ACP protocol
• OS: Windows11 (as per log paths)

Root Cause Analysis:
The write tool implementation lacks the necessary RPC response logic. After successfully writing the file, it should send a tool_call_update with status set to completed (or failed if an error occurs). However, no such update is transmitted, causing the client to wait indefinitely for a completion signal.

The edit and bash tools correctly send completion updates, which explains why those operations work without hanging.

This issue is independent of network timeouts or client-side problems; it is purely a server-side (agent) implementation flaw in the write tool.

Plugins

[email protected]

OpenCode version

v1.2.15 (binary opencode-windows-x64.zip)

Steps to reproduce

Key Log Evidence (from acp-transport-memory.log)

1. write tool call that hangs (no completion)
   2026-03-02 15:39:23,641 [2836043] FINE - AcpTransport - IN: {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"ses_35283b57dffeWINHDUV6qYRQOw","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_52f8706cb3434384a3905511","status":"in_progress","kind":"edit","title":"write","locations":[{"path":"D:\javaabel\Code\JavaCode\AI-DogV2\robot-platform\123.txt"}],"rawInput":{"content":"abc","filePath":"D:\javaabel\Code\JavaCode\AI-DogV2\robot-platform\123.txt"}}}}
   ... (no "completed" or "failed" update) ...
   2026-03-02 15:39:51,262 [2863664] FINE - AcpTransport - IN: {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"ses_35283b57dffeWINHDUV6qYRQOw","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_52f8706cb3434384a3905511","status":"failed","kind":"edit","title":"write","rawInput":{"content":"abc","filePath":"D:\javaabel\Code\JavaCode\AI-DogV2\robot-platform\123.txt"},"content":[{"type":"content","content":{"type":"text","text":"Tool execution aborted"}}],"rawOutput":{"error":"Tool execution aborted"}}}}
   Note: The failed status only appears after the client sent a session/cancel request.

2. edit tool call that completes normally
   2026-03-02 15:40:26,715 [2899117] FINE - AcpTransport - IN: {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"ses_35283b57dffeWINHDUV6qYRQOw","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_47a04cc2904b43a8b63b5ccb","status":"in_progress","kind":"edit","title":"edit","locations":[{"path":"D:\javaabel\Code\JavaCode\AI-DogV2\robot-platform\123.txt"}],"rawInput":{"filePath":"D:\javaabel\Code\JavaCode\AI-DogV2\robot-platform\123.txt","edits":[{"op":"append","lines":"测试"}]}}}}
   2026-03-02 15:40:26,747 [2899149] FINE - AcpTransport - IN: {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"ses_35283b57dffeWINHDUV6qYRQOw","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_47a04cc2904b43a8b63b5ccb","status":"completed","kind":"edit","content":[...]}}}

3. bash tool call that completes normally

2026-03-02 15:56:59,301 [3891703] FINE - AcpTransport - IN: {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"ses_35279d2c4ffeMLMaiiDATnI363","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_64ea5e96379b46b1854a2251","status":"in_progress","kind":"execute","title":"bash","locations":[],"rawInput":{"command":"rm "D:\javaabel\Code\JavaCode\AI-DogV2\robot-platform\abc.txt"","description":"删除abc.txt文件"}}}}
2026-03-02 15:56:59,611 [3892013] FINE - AcpTransport - IN: {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"ses_35279d2c4ffeMLMaiiDATnI363","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_64ea5e96379b46b1854a2251","status":"completed","kind":"execute","content":[...]}}}

Screenshot and/or share link

https://www.jetbrains.com/help/ai-assistant/2025.3/acp.html#install-agent-from-registry

acp.json:
{
"agent_servers": {
"OpenCode": {
"command": "D:\javaabel\Develop\opencode\opencode.exe",
"args": ["acp"]
}
}
}

Operating System

windows 11

Terminal

No response