Connect Claude

Add the person's MCP URL to Claude as a custom connector, or to Claude Code with one command.

Claude connects to custom connectors from Anthropic's cloud, not from the person's device, on claude.ai, Claude Desktop and the mobile apps alike. That is why a server running on the person's machine cannot be added as a connector, and why Relay's public URL can. Claude Code is the exception: it connects from the machine it runs on.

claude.ai and Claude Desktop#

Open Customize > Connectors (claude.ai/customize/connectors) and choose Add custom connector.
Enter a name, such as your app's name, and paste the MCP URL as the server URL.
Use no sign-in: choose No sign-in if the dialog asks how people connect, and leave the OAuth fields under Advanced settings empty.
Save. In a chat, turn the connector on from the + menu under Connectors.

Connectors belong to the Claude account, so one added on claude.ai also appears in Claude Desktop and the mobile apps.

WarningOn the Free plan a person can add one custom connector. On Team and Enterprise plans only an Owner adds custom connectors, for the whole organization, and every member who connects reaches the same URL. A Relay URL reaches one person's app, so on those plans use Claude Code or a personal plan.

Claude Code#

Run this command in a terminal:

⫻

shell

claude mcp add --transport http notes https://api.meslzy.com/relay/v1/mcp/ut_8Hq3Lm2Vx7Tc9Rb4Nw1Ks6Jd5Yf0Pg2E

Run /mcp inside Claude Code to check that the server is connected and see its tools. Add --scope user to make it available in every project instead of the current one.

Good to know#

Claude allows about 240 seconds per tool call, longer than Relay's 180, so Relay's limit decides.
Claude lists the tools when the connector is added. Relay answers from the tool list the app registered last, so the person can add the connector while the app is closed, once the app has connected one time.
A rotated URL makes the old one answer 404. Remove the connector and add it again with the new URL.