Replit Add MCP server: connect Sume with an X-API-Key header

Replit's Add MCP server flow takes an HTTPS endpoint, optional custom headers and Test and save. Connect Sume's hosted MCP and confirm the tools load.

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In Replit, choose Add MCP server, enter https://mcp.sume.com/mcp, open Advanced settings to add a header, and press Test and save. Replit's docs describe an HTTPS endpoint, custom headers such as X-API-Key, and Test and save completing OAuth when the server uses it. Sume accepts an API key as Authorization: Bearer or x-api-key, so both header styles work.

The Replit fields

Replit MCP form (read 2026-10-02)
FieldWhat to enter for Sume
Endpointhttps://mcp.sume.com/mcp (HTTPS)
Advanced settings, custom headerx-api-key with your Sume key
Test and saveConnects and, with OAuth, completes sign-in

Header or OAuth

With an API key header the agent sees the full tool set. With OAuth you consent on the MCP host: mcp:read is required, mcp:write is opt-in, and an attempt to write under read-only returns insufficient_scope. OAuth tokens are not API keys. Choose one method per connection.

Smoke test after saving

Ask the agent to list tools, or call them yourself.

  • mcp_health and account_me confirm the server and the account.
  • tools_list and tools_schema show argument names.
  • catalog_list shows what you can generate.
  • generate_image and generate_video are the router tools on hosted MCP; images_create and videos_create are not on it.

Long jobs from a Repl

A render outlasts one MCP call. Use jobs_wait, which holds at most 55 seconds, default 50, and on wait_slice_expired call it again with the same ids. Do not resubmit the paid create. A 524 or 522 means transport failure, not a failed job. Keep the key in Replit Secrets rather than in code, and give every paid call its own idempotency_key.

Sources

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