Unable to add MCP in VSCode GitHub Copilot

Checklist

  • I'm using the latest version of the extension (Run glab --version)
    • Extension version: glab 1.82.0 (b932a8d8)
  • Operating system and version: macOS 26.2 (25C56)
  • Gitlab.com or self-managed instance? self-managed instance
  • GitLab version (if self-managed) 18.5.4-ee (Use the version endpoint, like this: gitlab.my-company.com/api/v4/version)
  • I have performed glab auth status to check for authentication issues
  • Run the command in debug mode (like DEBUG=true glab mr list) and attach any useful output

Summary

When adding the MCP Server to VSCode GitHub Copilot with the config

"glab-mcp-server": {
  "type": "stdio",
  "command": "glab",
  "args": [
    "mcp",
    "serve"
  ]
}

the initialization works correctly but a prompt is sent this error appears

Failed to validate tool mcp_glab-mcp-serv_glab_api: Error: tool parameters array type must have items. Please open a Github issue for the MCP server or extension which provides this tool

Environment

  • OS: Darwin 25.2.0 arm64
  • SHELL: /bin/zsh
  • TERM: xterm-256color
  • GLAB: glab 1.82.0 (b932a8d8)

VSCode:

  • Version: 1.108.2 (Universal)
  • Commit: c9d77990917f3102ada88be140d28b038d1dd7c7
  • Date: 2026-01-21T13:52:09.270Z
  • Electron: 39.2.7
  • ElectronBuildId: 12953945
  • Chromium: 142.0.7444.235
  • Node.js: 22.21.1
  • V8: 14.2.231.21-electron.0
  • OS: Darwin arm64 25.2.0
  • copilot-chat extension version: 0.36.2

Steps to reproduce

Using VSCode with the Github Copilot chat extension add the glab mcp server as MCP Server. Enable the provided tools and send a prompt requesting information about anything related to GitLab (Ex: "Summary MR XXX")

What is the current bug behavior?

Error pops up

Failed to validate tool mcp_glab-mcp-serv_glab_api: Error: tool parameters array type must have items. Please open a Github issue for the MCP server or extension which provides this tool

What is the expected correct behavior?

No error and MCP tool are executed correctly

Relevant logs and/or screenshots

image

Possible fixes

https://gitlab.com/gitlab-org/cli/-/blob/main/internal/commands/mcp/serve/server.go?ref_type=heads#L227-247

Edited by Caio Ramos