API vs MCP for AI applications
Updated 27 September 2026.
Use the API when your application controls the HTTP call. Use MCP when an AI host should discover and call tools. Both return MySoMeData’s read-only social media data. The choice is about the caller, not about a second dataset.
A concrete split
- A product dashboard that refreshes numbers: API.
- An n8n workflow that posts a Monday summary to Slack: API. There is no native n8n node.
- A person asking Claude what changed last month: MCP.
- A Custom GPT with OAuth: neither raw MCP nor a key pasted in chat. It is an app authorization to the same layer.
What you tell the model in each case
With MCP, the host fetches tools, so the prompt can be the question. With the API, your application fetches JSON and can pass a smaller slice into the model. Either way, include the metric basis. Instagram reach, TikTok views, and Pinterest impressions are not interchangeable. The short version of this choice is API vs MCP.
What stays identical
OAuth to the platforms, normalization, the 365-day rolling window, calendar periods, and read-only scopes do not depend on the transport. Rotating an API key updates HTTP clients. MCP clients need their own reconnect if they stored that credential.