Claude Free plan has one custom connector: is Sume worth the slot?

Free Claude users can add one custom connector, and Sume's hosted MCP server is a reasonable thing to spend it on: one URL, https://mcp.sume.com/mcp, gives Claude read tools for jobs, assets, balance and the model catalog, and, once you opt in to write, image, video, music and speech generation. You never need a second connector to reach Sume, because the single endpoint carries every tool.

The plan limit comes from Anthropic's help article Get started with custom connectors using remote MCP, read on 2026-10-11. It says custom connectors using remote MCP are available on Claude, Cowork and Claude Desktop for Free, Pro, Max, Team and Enterprise plans, and that Free users are limited to one. Sume's side is from its MCP quickstart and OAuth and API keys pages.

How do I add Sume in the one slot?

Anthropic's article says to open Customize, then Connectors (Team and Enterprise owners use Organization settings, then Connectors), click Add, enter the remote MCP server URL, set authentication and finish. Use the Sume URL above. For authentication it lists OAuth, fixed credentials through request headers, and no sign-in. Sume's docs call OAuth the preferred path for interactive clients such as Claude, and the sign-in happens on Sume's MCP host, not on app.sume.com.

The same article says Claude connects to your server from Anthropic's cloud across its clients, and that servers on private networks must allow Anthropic's published IP ranges. Sume's endpoint is a public HTTPS URL, so nothing in Sume's docs asks you to allowlist anything.

What fits in one slot, and what does not?

Because the slot count is one, the question is what you lose by choosing Sume over another connector. The table compares the two Sume sign-in routes with the slot rule.

Why is the read-only default a good match?

A first connector deserves a safe start. With OAuth mcp:read, Sume exposes only read-only tools, so Claude can list jobs, read balance with balance_get and browse the catalog with catalog_list without being able to spend. Any call that changes data or generates media returns insufficient_scope until you grant mcp:write on the consent page.

When you do turn Write on, the spend gates still apply. Every write or paid call needs an idempotency_key, dry_run=true previews the cost, and the optional max_spend_usd is enforced when you send it. Ask Claude to dry-run first. Anthropic's article also advises disabling write-action tools when you use Research, which pairs well with a read-only grant.

What can Claude do with Sume on the first day?

Start with three read-only prompts. Ask Claude to call mcp_health and report the auth source, which should be mcp_oauth; to call tools_list and group the result by read and write; and to call account_me and balance_get so you see which workspace and how much balance the session is looking at. These calls cost nothing and prove the single slot is wired to the right account.

Then decide whether you need write. If the goal is to look at jobs and assets that colleagues or scripts already created, jobs_list, jobs_result and assets_list are all read tools, and read-only OAuth is enough. If the goal is to generate, reconnect with Write on and keep the first paid call small.

When should I leave the free plan or add a different route?

The slot limit only matters if you need a second remote server in Claude, such as a file store or a ticket system next to Sume. Anthropic's article does not say how a Free plan could keep two, so the practical options are paying for a plan that lifts the cap, or moving Sume's work to a route that does not use a connector slot. The MCP overview lists the Developer API and the CLI for backend and script use, and the same hosted endpoint also accepts an API key from any other remote MCP client.

If you stay on Free, test with tools_list and mcp_health first, as the quickstart suggests, and keep long renders in the jobs_wait pattern: each call holds up to 55 seconds, and you call it again with the same job id rather than creating the job twice.