[BUG] uild/packaging bug in Claude Code v2.1.51

Found 3 possible duplicate issues:

1. https://github.com/anthropics/claude-code/issues/28056
2. https://github.com/anthropics/claude-code/issues/28054
3. https://github.com/anthropics/claude-code/issues/28057

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🤖 Generated with Claude Code

Found the error in developer tools

__mainThreadExtensionService.ts:108__ Activating extension 'Anthropic.claude-code' failed: The argument 'filename' must be a file URL object, file URL string, or absolute path string. Received '__file:///home/runner/work/claude-cli-internal/claude-cli-internal/build-agent-sdk/sdk.mjs__'.
$onExtensionActivationError@__mainThreadExtensionService.ts:108__

Just uninstall and install older version.

I got same error.

[error] TypeError: The argument 'filename' must be a file URL object, file URL string, or absolute path string. Received 'file:///home/runner/work/claude-cli-internal/claude-cli-internal/build-agent-sdk/sdk.mjs'
    at Module.createRequire (node:internal/modules/cjs/loader:1915:13)
    at Object.<anonymous> (c:\Users\EndUser\.vscode\extensions\anthropic.claude-code-2.1.51-win32-x64\extension.js:45:4602)
    at Module._compile (node:internal/modules/cjs/loader:1714:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1848:10)
    at Module.load (node:internal/modules/cjs/loader:1448:32)
    at Module._load (node:internal/modules/cjs/loader:1270:12)
    at c._load (node:electron/js2c/node_init:2:17993)
    at e._load (file:///f:/vscode/072586267e/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:405:6055)
    at t._load (file:///f:/vscode/072586267e/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:223:22773)
    at s._load (file:///f:/vscode/072586267e/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:215:24706)
    at TracingChannel.traceSync (node:diagnostics_channel:328:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:244:24)
    at Module.require (node:internal/modules/cjs/loader:1470:12)
    at require (node:internal/modules/helpers:147:16)
    at pee.Cb (file:///f:/vscode/072586267e/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:254:1256)

Workaround: Downgrade to v2.1.49

Environment: Windows 11, VS Code, Claude Code extension v2.1.51

Problem

After a crash, the extension stopped working entirely with the error:

command 'claude-vscode.editor.openLast' not found

The extension fails to load when it can't restore a previous session, making it completely unusable.

What I tried (did NOT fix the issue)

1. Reload Window (Ctrl+Shift+P → Developer: Reload Window) — Error persisted.
2. Checked globalStorage at C:\Users\<user>\AppData\Roaming\Code\User\globalStorage\ — The anthropic.claude-code folder didn't exist, meaning the extension never re-initialized after the crash.
3. Full clean reinstall:

• Uninstalled the extension from VS Code.
• Manually deleted C:\Users\<user>\.vscode\extensions\anthropic.claude-code-*.
• Cleared VS Code cache (AppData\Roaming\Code\Cache and CachedData).
• Reinstalled from the Marketplace.
• Same error.

What fixed it

Downgrading to v2.1.49:

1. Go to Extensions (Ctrl+Shift+X) → Click on Claude Code.
2. Click the dropdown arrow next to the Uninstall button → "Install Another Version..."
3. Select version 2.1.49.
4. Restart VS Code.

The extension loaded correctly after the downgrade.

Suggestion

I'd recommend disabling auto-update for the extension to prevent it from updating back to the broken version:

• Extension gear icon → Auto Update → uncheck.

This seems to be a regression in v2.1.51 where the session restore logic doesn't handle missing or corrupted state gracefully.

Use Claude to Fix Claude works great if you want the new version lol

<img width="232" height="217" alt="Image" src="https://github.com/user-attachments/assets/f40b30da-23e8-4174-bf99-da8ba0a5b9fe" />

```# fix-claude-code-extension.ps1
#

Fixes Claude Code VSCode extension activation failure on Windows.

#

Error:

Activating extension 'Anthropic.claude-code' failed:

The argument 'filename' must be a file URL object, file URL string,

or absolute path string. Received 'file:///home/runner/work/...'

#

Root cause:

The extension bundle contains two hardcoded Linux CI build paths

(file:///home/runner/work/...). On Windows, Node.js rejects these

URLs in fileURLToPath() because they have no Windows drive letter.

This crashes the extension immediately at activation.

#

What this script patches:

Fix 1 - createRequire call: crashes at activation time

.createRequire("file:///home/runner/.../sdk.mjs")

-> .createRequire(__filename) (use actual file path instead)

#

Fix 2 - path resolution call: crashes when agent SDK is invoked

SomeFunc("file:///home/runner/.../sdk.mjs")

-> inline child_process lookup for the claude CLI on PATH

#

Usage:

Right-click -> "Run with PowerShell"

OR from a PowerShell prompt: .\fix-claude-code-extension.ps1

$ErrorActionPreference = "Stop"

$extensionRoot = "$env:USERPROFILE\.vscode\extensions"
$badUrl = 'file:///home/runner/work/claude-cli-internal/claude-cli-internal/build-agent-sdk/sdk.mjs'

---- Regex patterns (stable across minified versions) ----

Fix 1: .createRequire("file:///home/...sdk.mjs")

The method name createRequire is stable even in minified code.

$pattern1 = '\.createRequire\("file:///home/runner/work/claude-cli-internal/claude-cli-internal/build-agent-sdk/sdk\.mjs"\)'
$replacement1 = '.createRequire(__filename)'

Fix 2: anyMinifiedName("file:///home/...sdk.mjs")

After fix 1 removes the createRequire case, any remaining call

with this URL is the fileURLToPath wrapper (Ye or similar).

Replace it with an inline lookup that finds the claude CLI on PATH.

$pattern2 = '[a-zA-Z_$][a-zA-Z0-9_$]*\("file:///home/runner/work/claude-cli-internal/claude-cli-internal/build-agent-sdk/sdk\.mjs"\)'
$replacement2 = '(function(){try{return(require("child_process").spawnSync(process.platform==="win32"?"where.exe":"which",["claude"],{encoding:"utf8"}).stdout||"").split(/[\r\n]+/).filter(Boolean)[0]}catch(e){}})()'

---- Find extension directories ----

if (-not (Test-Path $extensionRoot)) {
Write-Host "VSCode extensions directory not found: $extensionRoot" -ForegroundColor Red
exit 1
}

$dirs = Get-ChildItem $extensionRoot -Directory | Where-Object { $_.Name -like 'anthropic.claude-code-*' }

if ($dirs.Count -eq 0) {
Write-Host "No Claude Code extension found in: $extensionRoot" -ForegroundColor Yellow
exit 1
}

Write-Host "Found $($dirs.Count) Claude Code extension(s):`n"

foreach ($dir in $dirs) {
$label = $dir.Name
$file = Join-Path $dir.FullName 'extension.js'

if (-not (Test-Path $file)) {
Write-Host "[$label] extension.js not found, skipping" -ForegroundColor Yellow
continue
}

$content = [System.IO.File]::ReadAllText($file, [System.Text.Encoding]::UTF8)

if ($content.IndexOf($badUrl) -lt 0) {
Write-Host "[$label] Not affected (bad URL not found) - already patched or different version" -ForegroundColor Green
continue
}

# Count occurrences before patching
$count = ([regex]::Matches($content, [regex]::Escape($badUrl))).Count
Write-Host "[$label] Found $count occurrence(s) of the bad CI path. Patching..." -ForegroundColor Cyan

# Backup original
$backup = "$file.bak"
Copy-Item $file $backup
Write-Host "[$label] Backup saved -> extension.js.bak"

# Apply Fix 1: createRequire
$patched = [regex]::Replace($content, $pattern1, $replacement1)
$fix1count = $count - ([regex]::Matches($patched, [regex]::Escape($badUrl))).Count
Write-Host "[$label] Fix 1 (createRequire): replaced $fix1count occurrence(s)"

# Apply Fix 2: fileURLToPath wrapper
$patched2 = [regex]::Replace($patched, $pattern2, $replacement2)
$fix2count = ([regex]::Matches($patched, [regex]::Escape($badUrl))).Count `

• ([regex]::Matches($patched2, [regex]::Escape($badUrl))).Count

Write-Host "[$label] Fix 2 (path resolver): replaced $fix2count occurrence(s)"

# Verify no bad URLs remain
$remaining = ([regex]::Matches($patched2, [regex]::Escape($badUrl))).Count
if ($remaining -gt 0) {
Write-Host "[$label] WARNING: $remaining occurrence(s) still remain after patching!" -ForegroundColor Yellow
}

# Write patched file
[System.IO.File]::WriteAllText($file, $patched2, [System.Text.Encoding]::UTF8)
Write-Host "[$label] Patched successfully" -ForegroundColor Green
Write-Host ""
}

Write-Host "Done. Reload VSCode to apply: Ctrl+Shift+P -> 'Developer: Reload Window'" -ForegroundColor White

Hi, sorry about the disruption. We just published v2.1.52 which should hopefully work better.

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.