Lovable custom MCP connector for Sume: API key, chat only

You can add Sume to Lovable as a custom remote MCP server on any plan, authenticate with a bearer token or API key, and use it from project chat. It will not run inside a published app. Lovable's docs say chat connectors give context only in project chat and do not power published apps. The server URL is https://mcp.sume.com/mcp, a streamable HTTP endpoint.

What Lovable's pages say

Setting it up with a Sume key

Create a Sume API key, choose the bearer or API-key option in Lovable, and paste the endpoint. An API key sees the full tool set, including write and paid tools, so create a key you are comfortable giving a chat. Alternatively use OAuth, which asks for consent on the MCP host: mcp:read is required and read-only, mcp:write is opt-in, and mutating tools return insufficient_scope under read-only.

• Run tools_list and account_me first to confirm the connection.
• Use catalog_list before any paid generation.
• Paid and write tools need idempotency_key; use dry_run and max_spend_usd to preview cost.

Because it is chat only

An MCP connector in Lovable helps you build, for example by generating a hero video you then add to the project as an asset. The shipped app cannot call the connector at runtime. For runtime generation, your app's backend must call the Sume API with a server-side key, never one in browser code.

Jobs are asynchronous. A request returns a job id; jobs_wait waits at most 55 seconds per call, and wait_slice_expired means call again with the same ids.

Pitfalls

Static outbound IPs are Enterprise only on Lovable, so do not rely on an IP allow list at Sume's side. Connections are personal, so each teammate sets up their own, and a leaving teammate's key should be revoked on the Sume side.