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How to actually do it

Should I use a tool's MCP server or its REST API?

The short answer

Use the MCP server when it exists and exposes what you need: it is faster to wire, and any client can use it. Use the REST API when you need something the server does not expose, when you want tight control over rate limits and error handling, or when there is no server at all, which is the case for 117 of 293 entries here.

What each one gives you

MCP server REST API plus your own wrapper
Time to first callMinutes, if a server existsHours to days
Who decides the surfaceThe vendorYou
Reuse across clientsAny MCP clientWhatever you wrote it for
Rate limit and retry controlWhatever the server doesYours
Breaks whenThe vendor changes the serverThe vendor changes the API
Available for165 of 293 entries here Most of the rest, if they document one

The honest default

Start with the server if there is one. The whole point of a protocol is that you stop writing the same integration twice, and 144 vendors here have already done the work for you. Move to the API when you hit a specific wall, and you will know exactly which wall it was.

When the API is clearly right

The thing that decides it more often than either

The access gate. 45 entries need a contract before you get any credential at all, and at that point the protocol question is academic. Check the gate before you design either integration.

Sources

Every number on this page is generated from directory.json at build time and carries the date it was baked: 2026-08-25. Nothing is typed by hand, nothing is rounded, and nothing is estimated. The underlying data is published in full. Where the honest answer is a zero, the zero is printed.

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