Authentication

How to authenticate with the MCP server to access community tools

Palette generation tools work without any credentials. Community tools — publishing, updating, deleting, or listing your own palettes — require a valid UI Color Palette account.

How it works

The server implements OAuth 2.0 with dynamic client registration. The authorization server is Supabase, proxied through the MCP worker so that MCP clients see a single issuer.

Endpoint	Path
Discovery	/.well-known/oauth-authorization-server
Client registration	/oauth/register
Token exchange	/oauth/token
MCP	/mcp

MCP clients that support OAuth 2.0 (Claude Desktop, Cursor, etc.) handle the full flow automatically — you just sign in when prompted.

Bearer token

If your client does not handle OAuth automatically, you can pass an access token directly:

Authorization: Bearer <your-access-token>

The token is read from the Authorization header on the /mcp request and stored in durable state for the duration of the session.

Which tools require authentication

Tool	Auth required
get_palette	No
get_color_system	No
create_color_harmony	No
extract_dominant_colors	No
generate_code	No
generate_colors_from_prompt	No
preview_palette	No
list_published_palettes	No
list_my_published_palettes	Yes
get_published_palette	No
publish_palette	Yes
update_published_palette	Yes
share_published_palette	Yes
unshare_published_palette	Yes
unpublish_palette	Yes

When a tool requires authentication and no token is present, the server returns:

{ "error": "Authentication required. Please sign in via OAuth to use this tool." }