[FEATURE]: Add MCP OAuth authentication UI to settings

[aaranmcguire]

Feature Request

Problem

Currently, users have no UI-based way to manage OAuth credentials for MCP (Model Context Protocol) servers. Authentication must be done through command-line tools or by manually editing configuration files, which is not user-friendly.

Proposed Solution

Add a dedicated MCP settings tab to the OpenCode settings dialog that allows users to:

• View all configured MCP servers and their authentication status
• Authenticate with OAuth-enabled MCP servers via browser flow
• Re-authenticate existing servers when credentials expire
• Logout/remove stored OAuth credentials
• See real-time authentication status updates

Benefits

• Improved UX: Users can manage MCP server authentication through a visual interface
• Discoverability: Users can see which servers need authentication
• Error visibility: Clear error messages when authentication fails
• Convenience: No need to use CLI commands for OAuth flows

Use Case

When a user adds an MCP server that requires OAuth (e.g., GitHub, Google Drive, Jira), they need an easy way to authenticate and manage those credentials without leaving the application.

Related

• Related to existing MCP OAuth infrastructure
• Complements existing command-line OAuth functionality
• Part of improving overall MCP user experience

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• [FEATURE]: Allow custom OAuth redirect URI configuration for MCP servers #7377: [FEATURE]: Allow custom OAuth redirect URI configuration for MCP servers (related OAuth MCP configuration feature)
• [FEATURE]: Easily import settings/agents/MCP servers from other tools #6207: [FEATURE]: Easily import settings/agents/MCP servers from other tools (includes MCP server management/configuration UI improvements)
• Import settings from Claude Code #10305: Import settings from Claude Code (includes MCP server/config management)

Feel free to ignore if none of these address your specific case.