[Bug&FR] VSCode Copilot Agent Hook Compability

[KagaJiankui]

Problem

当前提供的ccplugin不兼容VSCode Copilot提供的cc hook兼容层，会阻塞Copilot的回复导致Copilot完全无响应。禁用memsearch ccplugin后恢复正常。

Copilot Agent Hook日志如下：

026-03-23 16:38:04.354 [info] [#2] [UserPromptSubmit] Executing 1 hook(s)
2026-03-23 16:38:04.354 [info] [#2] [UserPromptSubmit] Running: {"command":"bash c:\\Users\\Falke\\AppData\\Roaming\\Code\\agentPlugins\\github.com\\zilliztech\\memsearch\\ccplugin/hooks/user-prompt-submit.sh","cwd":{"$mid":1,"fsPath":"d:\\Electronics\\batt_data","_sep":1,"external":"file:///d%3A/Electronics/batt_data","path":"/d:/Electronics/batt_data","scheme":"file"},"env":{"CLAUDE_PLUGIN_ROOT":"c:\\Users\\Falke\\AppData\\Roaming\\Code\\agentPlugins\\github.com\\zilliztech\\memsearch\\ccplugin"},"timeout":15}
2026-03-23 16:38:04.354 [info] [#2] [UserPromptSubmit] Input: {"timestamp":"2026-03-23T08:38:04.338Z","hook_event_name":"UserPromptSubmit","session_id":"7a2de734-a7e3-4cfe-904c-b81366dc5add","transcript_path":"c:\\Users\\Falke\\AppData\\Roaming\\Code\\User\\workspaceStorage\\819b23ec1d9876c2b8c00f4113d7dc24\\GitHub.copilot-chat\\transcripts\\7a2de734-a7e3-4cfe-904c-b81366dc5add.jsonl","prompt":"在 #file:docs 下编写当前主分支进度：\r\n\r\n泛化实验结果：25 度 1370 钠电池、40 度 1370 钠电池。25度18650锂电池两个，40度18650锂电池一个，45度18650锂电池一个，对于 HPPC 放电曲线的平台段跟踪能力都很强，优于全程单一PSO离线结果或单一SOC-OCV模型\r\n\r\n消融实验结果：在 25 度 1370 钠电池上进行了消融实验，分别使用单一高次多项式、单一指数核函数、分段高次多项式和分段不同参数 PSO 估计，实验结果是分段不同参数不同 SOC-OCV 关系式优于分段同一参数不同多项式优于分段高次多项式。\r\n\r\n新方法（正在进行代码编写）：研究了用于SOC-OCV建模的函数，分三个新方向：使用LM法拟合指数和多项式，使用LM或VARPRO法拟合统一sigmoid模型\r\n\r\n最后还差一个全程用同一个多项式但是分段两次 PSO的消融实验","cwd":"d:\\Electronics\\batt_data"}
2026-03-23 16:38:04.374 [info] [HookExecutor] Hook command was cancelled: bash c:\Users\Falke\AppData\Roaming\Code\agentPlugins\github.com\zilliztech\memsearch\ccplugin/hooks/user-prompt-submit.sh
2026-03-23 16:38:04.374 [info] [#2] [UserPromptSubmit] Completed (NonBlockingError) in 36ms, no output
2026-03-23 16:39:05.012 [info] [#3] [SessionStart] Executing 1 hook(s)
2026-03-23 16:39:05.012 [info] [#3] [SessionStart] Running: {"command":"bash c:\\Users\\Falke\\AppData\\Roaming\\Code\\agentPlugins\\github.com\\zilliztech\\memsearch\\ccplugin/hooks/session-start.sh","cwd":{"$mid":1,"fsPath":"d:\\Electronics\\batt_data","_sep":1,"external":"file:///d%3A/Electronics/batt_data","path":"/d:/Electronics/batt_data","scheme":"file"},"env":{"CLAUDE_PLUGIN_ROOT":"c:\\Users\\Falke\\AppData\\Roaming\\Code\\agentPlugins\\github.com\\zilliztech\\memsearch\\ccplugin"},"timeout":10}
2026-03-23 16:39:05.012 [info] [#3] [SessionStart] Input: {"timestamp":"2026-03-23T08:39:05.001Z","hook_event_name":"SessionStart","session_id":"0109d189-b26f-4652-899c-ba993499a71b","transcript_path":"c:\\Users\\Falke\\AppData\\Roaming\\Code\\User\\workspaceStorage\\819b23ec1d9876c2b8c00f4113d7dc24\\GitHub.copilot-chat\\transcripts\\0109d189-b26f-4652-899c-ba993499a71b.jsonl","source":"new","cwd":"d:\\Electronics\\batt_data"}
2026-03-23 16:39:12.048 [info] [HookExecutor] Hook command was cancelled: bash c:\Users\Falke\AppData\Roaming\Code\agentPlugins\github.com\zilliztech\memsearch\ccplugin/hooks/session-start.sh
2026-03-23 16:39:12.048 [info] [HookExecutor] Hook command returned non-JSON output: bash c:\Users\Falke\AppData\Roaming\Code\agentPlugins\github.com\zilliztech\memsearch\ccplugin/hooks/session-start.sh
2026-03-23 16:39:12.048 [info] [#1] [SessionStart] Completed (Success) in 75371ms
2026-03-23 16:39:12.048 [info] [#1] [SessionStart] Output: {"systemMessage": "[memsearch v0.1.19] embedding: openai/embedding-3 | milvus: https://in05-f0e8107461437ec.serverless.ali-cn-hangzhou.cloud.zilliz.com.cn | collection: ms_batt_data_fc49d98f", "hookSpecificOutput": {"hookEventName": "SessionStart", "additionalContext": "# Recent Memory\n\n## 2026-03-23.md\n
## Session 00:12


## Session 06:02


## Session 15:23


## Session 15:26


## Session 16:33


## Session 16:38\n\n## 2026-03-22.md\n
## Session 22:41\n\n"}}

使用的bash为Git bash。

Proposed solution

实现与VSCode copilot提供的plugin和hook兼容层的兼容。

Alternatives considered

No response

[zc277584121]

Thanks for the detailed logs — very helpful!

From the logs, memsearch is actually working correctly — SessionStart returned valid JSON with your memory context. The main issue is latency: remote Milvus (Zilliz Cloud) + remote OpenAI embedding makes session-start.sh take ~75s, which exceeds the Copilot hook timeout.

Quick fix to try: switch to local ONNX embedding + Milvus Lite. This eliminates all network round-trips and should bring SessionStart down to a few seconds:

# ~/.memsearch/config.toml
[embedding]
provider = "onnx"

[milvus]
uri = "~/.memsearch/milvus.db"

Then reinstall with ONNX support: uv tool install memsearch[onnx]

A couple of questions to help us understand the Copilot compatibility layer better:

1. Is there documentation for the Copilot Agent hook compatibility layer? (timeout behavior, supported hook events, etc.)
2. The UserPromptSubmit hook was cancelled after 36ms with NonBlockingError — do you know if Copilot treats this hook type differently from SessionStart?

We're actively planning multi-platform support (including VSCode Copilot), so this feedback is very valuable.

[KagaJiankui]

I'm using Windows thus the local Milvus option is not available for me currently. And invoking memsearch backend in command line did not take 75000ms before receiving responses from remote endpoints.

For additional question 1, there are two doc entries from GitHub and VSCode official doc site

• https://code.visualstudio.com/docs/copilot/customization/hooks
• https://docs.github.com/en/copilot/how-tos/use-copilot-agents/coding-agent/use-hooks

For additional question 2, I have no idea how to grab related information within run-time, the best options I can list is either read the source of @microsoft/copilot-chat and @microsoft/copilot and @microsoft/vscode or inject native debugging module to V8

[KagaJiankui]

By investigating the Claude Code plugin hook scripts, the root cause can be pinpointed on my machine:

1. the transcript parsing utility requires python3.exe which is uncommon in windows installation of python, whatever miniconda or standalone version.
   • Solution: Use New-Item -ItemType SymbolicLink / mklink create the symbolic link manually
2. The transcript format of the old version of Claude might be: {"type":"user", "message": {"content": "..."}}. However, the new version of Claude changed to a flat structure: {"type":"user", "content": "..."}
   • Solution: Add parsing for fields in the new flat format: content = obj.get("message", {}).get("content") or obj.get("content").
   • Modification point: parse-transcript.sh, Ln 47 and 74
3. The path format of Git/MinGW bash is incompatible for python filesystem operations on Windows.
   • Solution: Use cygpath -u/-w/-m built-in utility to ensure path format compatibility.