Base44 custom MCP connection: add Sume's hosted server

To add Sume to Base44, open Account preferences, go to Builder, then MCP Connections, click Add custom MCP, enter https://mcp.sume.com/mcp as the URL, and choose either OAuth or a custom header. Base44 says custom MCP connections need a Builder plan or higher, and an account can connect up to 20 MCP servers. Once the connection tests clean, the Base44 AI chat can call Sume's hosted tools for images, video and audio while you build.

What are the exact steps in Base44?

Base44's documentation lists the path: click the workspace name at the bottom left, open Account preferences, then Builder, then MCP Connections, then Add custom MCP. Fill in a name, the URL and the authentication, click Test, and click Test and add to save.

• Name: anything your collaborators will recognize, for example Sume.
• URL: https://mcp.sume.com/mcp. This is the production endpoint on the Sume docs.
• Authentication: OAuth, or Not required plus a custom header. Sume does not allow unauthenticated calls, so skip Not required unless you add a header.
• Custom header: Base44 lets you add a header name and value. Sume accepts x-api-key or Authorization: Bearer.

Which auth should you pick: OAuth or an API key header?

Both work with Sume's hosted MCP, and they give different tool sets. OAuth grants mcp:read by default, so the session sees read-only tools only. To expose the tools that change data and the paid generation tools, the person approving must turn on the Write toggle on the consent page. An API key session sees the full hosted tool set. Sume has no mcp:paid scope, so spend is controlled by wallet admission, and paid calls still need an idempotency_key.

If a teammate only needs to browse jobs and assets from the Base44 chat, OAuth with Write off is the safer default. Base44 itself notes that OAuth is completed after the initial setup, so plan for a browser sign-in on the Sume MCP host.

What can Base44 do with Sume after connecting?

Base44 states that MCP connections only control what the AI chat can access while you build. They do not work in app logic, workflows or runtime, and data fetched during building is static. For Sume that means the chat can generate a hero image, a clip or a voice-over while you build, then you store the resulting media.sume.com URL in your app. A published Base44 app does not call the connection at runtime.

Quick reference

Test it before you generate anything

After saving, ask the chat to call mcp_health and tools_list. Both are read-only and free. Before a paid call, ask for dry_run=true or generation_admission_preview to see the estimate. Long video jobs outlast one call, so tell the chat to resume with jobs_wait using the same job id and never to submit the create again.