Chat preflight fails on UNC (network share) workspaces: stat '\\server\.git\' throws UNKNOWN (Windows)

[no7749]

Kimi Code Extension: UNC .git Bug — Diagnosis & Patch Guide

Recorded 2026-08-02 (Windows 11 ARM64, Acer) while fixing this on a Windows machine.
Written to be reusable on other machines — read the "Notes for macOS" section first if you are on a Mac.

Symptom

• Kimi Code extension (VS Code / Antigravity) works in exactly one project (NintendoBot) and fails everywhere else.
• In every other window: typing a message and pressing send does nothing — the text stays in the input box, no visible error on screen.
• Uninstalling / reinstalling the extension does not help (it is a code bug, not corrupted state).

How to diagnose (repeatable on any machine)

1. In a broken window, try to send one message.

2. Open the Command Palette (Ctrl+Shift+P / macOS Cmd+Shift+P) → run Kimi Code: Show Logs.

3. If you see this line repeated on every send attempt, it is this exact bug:

   Chat preflight request failed: KimiError: UNKNOWN: unknown error, stat '\\ds923\.git\'
   

   (The path differs per machine — it is <server>\.git of whatever file server the workspace lives on.)

Root cause

1. On send, the extension creates a session → loads the MCP config → calls findProjectRoot(cwd), which walks up parent directories probing for .git (git root detection).
2. If the workspace is on a NAS via a UNC path, e.g. \\ds923\SomeShare\Folder, and has no .git, the walk climbs past the share root and stats \\ds923\.git\ — i.e. it asks server ds923 for a share literally named .git, which does not exist.
3. Node/libuv on Windows reports this with error code UNKNOWN (not the usual ENOENT).
4. pathExists$2 in dist/extension.js only swallows ENOENT/ENOTDIR; every other error is rethrown → preflight fails → the message is never sent.
5. NintendoBot survived because it is a git repo — .git is found at the first level and the walk never reaches the UNC share root.

Reproduce with plain Node (proves it is not machine-specific)

// test_unc_stat.js — run with: node test_unc_stat.js
const fs = require('fs');
try {
  fs.statSync('\\\\ds923\\.git\\');
  console.log('OK');
} catch (e) {
  console.log('FAIL ->', e.code, '|', e.message);
  // Windows: FAIL -> UNKNOWN | UNKNOWN: unknown error, stat '\\ds923\.git\'
}

The patch (applied 2026-08-02 on the Windows machine)

One line in the extension's dist/extension.js:

 async function pathExists$2(filePath) {
 	try {
 		await stat$2(filePath);
 		return true;
 	} catch (error) {
 		if (isPathMissing$1(error)) return false;
-		throw error;
+		return false;
 	}
 }

Location in version 0.6.7: region header //#region ../../packages/agent-core/src/mcp/config-loader.ts
(around byte offset 5497726 — search for pathExists$2 or isPathMissing).

Steps

# 1. Go to the extension folder (Windows example)
cd "/c/Users/<user>/.vscode/extensions/moonshot-ai.kimi-code-<version>/dist"

# 2. Back up the original file
cp extension.js extension.js.bak-unc-fix

# 3. Edit: find "if(isPathMissing$1(error))return false;throw error"
#    and change "throw error" to "return false" (inside pathExists$2 only).
#    ⚠️ Minified variable names may differ across versions — search by context:
#    "pathExists" + "isPathMissing" + "throw error" close together.

# 4. Syntax check (important: the bundle is ESM — you need --input-type=module)
node --check --input-type=module < extension.js && echo SYNTAX_OK

# 5. Reload every IDE window (Developer: Reload Window) or restart the app

Repeat for every IDE that has its own copy of the extension

Each IDE keeps a separate copy (same version = byte-identical file, so you can copy the already-patched file over — back up first):

IDE	Windows	macOS
VS Code	%USERPROFILE%\.vscode\extensions\moonshot-ai.kimi-code-*	~/.vscode/extensions/moonshot-ai.kimi-code-*
Antigravity	%USERPROFILE%\.antigravity-ide\extensions\moonshot-ai.kimi-code-*	~/.antigravity-ide/extensions/moonshot-ai.kimi-code-*

# Example: copy the patched file over Antigravity's copy (after md5sum confirms the originals match)
cp <antigravity>/dist/extension.js <antigravity>/dist/extension.js.bak-unc-fix
cp <vscode>/dist/extension.js <antigravity>/dist/extension.js
node --check --input-type=module < <antigravity>/dist/extension.js && echo SYNTAX_OK

Notes for macOS

• This bug may not occur on macOS at all — macOS mounts network shares under /Volumes/<share>, a normal POSIX path. The .git walk terminates at /, and stat returns plain ENOENT, which the code already handles. No UNKNOWN error.
• So test first, don't patch blindly: open a non-git project stored on the NAS and try sending a message.
  • Works fine → nothing to do.
  • Same symptom → check the log (Kimi Code: Show Logs) for the same error, then apply the patch steps above.
• You can probe with the Node script above using the real mount path, e.g. /Volumes/.git.
• The macOS extension build is darwin-arm64 / darwin-x64; the bundle structure is the same. Search with: grep -ao '.\{80\}pathExists\$2.\{80\}' extension.js

Rollback

cd <extension>/dist
cp extension.js.bak-unc-fix extension.js
# then reload the window

Caveats

• The patch is overwritten when the extension auto-updates. If the symptom returns after an update, the new version still has the bug — re-apply this patch.
• The truly permanent fix is upstream: report the bug (drafts below) to Moonshot.
• The bundle contains a second copy of the same pattern (pathExists$1 in agent-core-v2, around byte 7462143) that also rethrows. It was not patched (minimal-change principle — it is not the code path that caused this symptom). If a similar error with a different message ever appears, revisit that one.

---

Draft: Bug report email to Moonshot (code@moonshot.ai)

To: code@moonshot.ai
Subject: Bug: VS Code extension 0.6.7 — chat fails on UNC (network share) workspaces: stat '\\server\.git\' throws UNKNOWN

Hi Kimi Code team,

Found a bug in the VS Code extension (moonshot-ai.kimi-code 0.6.7, win32-arm64)
that makes chat completely unusable for any workspace opened via a UNC path
(Windows network share, e.g. a NAS) that is not a git repository.

## Symptom

Typing a message and pressing send does nothing — the text stays in the input
box. The log ("Kimi Code: Show Logs") shows, on every send attempt:

    Chat preflight request failed: KimiError: UNKNOWN: unknown error, stat '\\ds923\.git\'

Reinstalling the extension does not help.

## Root cause

During chat preflight, session creation loads the MCP config
(packages/agent-core/src/mcp/config-loader.ts), which calls findProjectRoot(cwd).
That function walks up parent directories probing for ".git" using pathExists():

    async function pathExists(filePath) {
        try {
            await stat(filePath);
            return true;
        } catch (error) {
            if (isPathMissing(error)) return false;  // only ENOENT/ENOTDIR
            throw error;                             // <-- everything else escapes
        }
    }

For a workspace at \\ds923\SomeShare\Folder (server "ds923", share "SomeShare"),
the walk climbs past the share root and stats \\ds923\.git\ — i.e. it asks the
server for a share literally named ".git". On Windows, Node/libuv surfaces this
as a SystemError with code UNKNOWN (UV_UNKNOWN), not ENOENT, so pathExists
rethrows and the whole preflight fails.

A workspace that IS a git repo works fine, because .git is found at the first
level and the walk never reaches the UNC share root.

## Minimal reproduction (plain Node on Windows, no extension involved)

    const fs = require('fs');
    try {
      fs.statSync('\\\\ds923\\.git\\');
    } catch (e) {
      console.log(e.code, '|', e.message);
      // -> UNKNOWN | UNKNOWN: unknown error, stat '\\ds923\.git\'
    }

(Any Windows machine with a SMB share; replace ds923 with the server name.)

## Suggested fix

pathExists() should treat ANY stat failure as "not found" (return false),
not just ENOENT/ENOTDIR — a probe for an optional marker file should never
throw. Alternatively, findProjectRoot() should stop the upward walk at the
UNC share root.

Note: a second copy of the same pattern exists in the agent-core-v2 code path
(another pathExists that rethrows non-missing errors) — likely worth fixing
both.

## Workaround applied locally

I patched dist/extension.js (changed `throw error` to `return false` in that
one function) and chat now works in all UNC workspaces. Happy to provide more
logs if useful.

Environment: Windows 11 ARM64, VS Code + Antigravity, extension 0.6.7,
workspace on Synology NAS via SMB (\\ds923\...).

Thanks!

Keep this file after sending — if they reply asking for more logs, everything is in here.

---

Draft: GitHub Issue (recommended — use this one)

Open: https://github.com/MoonshotAI/kimi-code/issues/new
Title: Chat preflight fails on UNC (network share) workspaces: stat '\\server\.git\' throws UNKNOWN (Windows)
Body: copy only the part inside the fence below

## Bug description

On Windows, the VS Code extension (moonshot-ai.kimi-code 0.6.7, win32-arm64)
cannot send any chat message when the workspace is opened via a **UNC path**
(network share, e.g. a NAS) **and is not a git repository**. Typing a message
and pressing send does nothing — the text stays in the input box.

Workspaces that are git repositories work fine, which made this look
environment-specific at first. Reinstalling the extension does not help.

## Log output

`Kimi Code: Show Logs` shows this on **every** send attempt:

```
Chat preflight request failed: KimiError: UNKNOWN: unknown error, stat '\\ds923\.git\'
```

## Root cause

During chat preflight, session creation loads the MCP config
(`packages/agent-core/src/mcp/config-loader.ts`) → `findProjectRoot(cwd)` walks
up parent directories probing for `.git` via `pathExists()`:

```js
async function pathExists(filePath) {
    try {
        await stat(filePath);
        return true;
    } catch (error) {
        if (isPathMissing(error)) return false;  // only ENOENT/ENOTDIR
        throw error;                             // ← everything else escapes
    }
}
```

For a workspace at `\\ds923\SomeShare\Folder` (server `ds923`, share
`SomeShare`), the walk climbs **past the share root** and stats
`\\ds923\.git\` — i.e. it asks the server for a share literally named `.git`.
On Windows, Node/libuv surfaces this as a `SystemError` with code **UNKNOWN**
(`UV_UNKNOWN`), not `ENOENT`. `pathExists` rethrows it, preflight fails, and
the message is never sent.

A git-repo workspace survives because `.git` is found at the first level and
the walk never reaches the UNC share root.

## Minimal reproduction (plain Node, no extension involved)

Any Windows machine with an SMB share (replace `ds923` with the server name):

```js
const fs = require('fs');
try {
  fs.statSync('\\\\ds923\\.git\\');
} catch (e) {
  console.log(e.code, '|', e.message);
  // → UNKNOWN | UNKNOWN: unknown error, stat '\\ds923\.git\'
}
```

## Expected behavior

`pathExists()` treats **any** stat failure as "not found" (a probe for an
optional marker file should never throw), and/or `findProjectRoot()` stops
the upward walk at the UNC share root.

## Suggested fix

```diff
     } catch (error) {
         if (isPathMissing(error)) return false;
-        throw error;
+        return false;
     }
```

Note: a second copy of the same pattern exists in the agent-core-v2 code path
(another `pathExists` that rethrows non-missing errors) — worth fixing both.

## Environment

- OS: Windows 11 ARM64
- Extension: moonshot-ai.kimi-code 0.6.7 (win32-arm64) — also reproduced in Antigravity
- Workspace: Synology NAS via SMB (`\\ds923\...`)

## Local workaround (confirmed working)

Patching `dist/extension.js` with the one-line change above fixes chat in all
UNC workspaces; behavior in normal (git) workspaces is unchanged.