Preflight Checklist
What's Wrong?
The Claude in Chrome extension has never successfully connected to the Claude Desktop application on Windows, in any mode (chat, Claude Code, or Cowork). Every tab operation returns No tab available immediately, with no additional detail.
The Chrome extension itself is fully functional — Claude operates correctly from the browser sidebar, can navigate pages, interact with elements, and fill forms. The broken link is specifically between the extension and Claude Desktop.
What Should Happen?
Claude Desktop should be able to list, access, and interact with open Chrome tabs via the extension, across all modes.
Error Messages / Logs
All tab operations return the same error with no further detail:
Exact calls attempted and responses:
| Tool call |
Input |
Response |
browser_batch → tabs_list |
{} |
Error: No tab available |
browser_batch → tabs_context_mcp |
{"createIfEmpty": false} |
Error: No tab available |
browser_batch → tabs_context_mcp |
{"createIfEmpty": true} |
Error: No tab available |
browser_batch → screenshot |
{} |
Error: No tab available |
Note: createIfEmpty: true should create a new tab group from scratch — its failure suggests the MCP server has no connection to the extension whatsoever, not merely a missing tab group.
Tools present (3): browser_batch, tabs_close_mcp, file_upload
Tools absent: navigate, read_page, click, find, javascript_tool, tabs_context_mcp, screenshot, and all other interaction tools
This degraded 3-tool state superficially resembles what was reported in #38783, although that issue affects computer use, an entirely different component.
Steps to Reproduce
- Install Claude Desktop on Windows and sign in
- Install the Claude in Chrome extension (v1.0.68) in Chrome
- Verify the extension works — open the sidebar in Chrome, confirm Claude can interact with page content
- Open Claude Desktop in any mode (chat, Claude Code, or Cowork)
- Open Chrome with at least one active tab
- Attempt any tab operation (navigate, screenshot, tabs_context_mcp, etc.)
- Observe:
Error: No tab available regardless of mode or call
System Information
- Claude Desktop version: 2.1.111 (
claude --version)
- Claude in Chrome extension version: 1.0.68
- Chrome version: 147.0.7727.102 (Official Build) (64-bit)
- OS: Windows
- API platform: Anthropic (direct)
- Regression: No — has never worked on this machine since initial install
Why This Is Different From Related Issues
Additional Context
- The extension↔Desktop bridge appears entirely non-functional on Windows from first install, suggesting a possible issue with native messaging host registration on Windows during installation
- Environment confirms
CLAUDE_CODE_HOST_PLATFORM=win32
Preflight Checklist
What's Wrong?
The Claude in Chrome extension has never successfully connected to the Claude Desktop application on Windows, in any mode (chat, Claude Code, or Cowork). Every tab operation returns
No tab availableimmediately, with no additional detail.The Chrome extension itself is fully functional — Claude operates correctly from the browser sidebar, can navigate pages, interact with elements, and fill forms. The broken link is specifically between the extension and Claude Desktop.
What Should Happen?
Claude Desktop should be able to list, access, and interact with open Chrome tabs via the extension, across all modes.
Error Messages / Logs
All tab operations return the same error with no further detail:
Exact calls attempted and responses:
browser_batch→tabs_list{}Error: No tab availablebrowser_batch→tabs_context_mcp{"createIfEmpty": false}Error: No tab availablebrowser_batch→tabs_context_mcp{"createIfEmpty": true}Error: No tab availablebrowser_batch→screenshot{}Error: No tab availableNote:
createIfEmpty: trueshould create a new tab group from scratch — its failure suggests the MCP server has no connection to the extension whatsoever, not merely a missing tab group.Tools present (3):
browser_batch,tabs_close_mcp,file_uploadTools absent:
navigate,read_page,click,find,javascript_tool,tabs_context_mcp,screenshot, and all other interaction toolsThis degraded 3-tool state superficially resembles what was reported in #38783, although that issue affects computer use, an entirely different component.
Steps to Reproduce
Error: No tab availableregardless of mode or callSystem Information
claude --version)Why This Is Different From Related Issues
No tab availablesymptom, but macOS only. Described as a regression wheretabs_context_mcplists tabs successfully before other calls fail. In our case,tabs_context_mcpitself fails immediately. Platform and failure mode differ.Additional Context
CLAUDE_CODE_HOST_PLATFORM=win32