# What's the difference between MCP and a plain API call?

With a direct API integration, your code names the endpoint and request shape. An MCP client asks a server what tools it offers, reads their schemas, then calls one. [You can run that MCP server yourself](https://ts.sdk.modelcontextprotocol.io/v2/get-started/first-server), just as you can call [someone else's plain API](https://docs.stripe.com/api).

An MCP client can keep building calls against a stale `tools/list` result after the server changes its schema. A direct API integration can break when a vendor changes an endpoint your code still calls. The [cached MCP tool list](/answers/mcp-tool-reliability/what-happens-when-an-mcp-server-changes-its-tool-schema) is the difference to inspect; server ownership tells you neither contract is safe from change.

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Sources:
- Model Context Protocol TypeScript SDK: Build your first server: https://ts.sdk.modelcontextprotocol.io/v2/get-started/first-server (fetched 2026-09-25)
- Stripe API reference: https://docs.stripe.com/api (fetched 2026-09-25)

Source: https://tessary.ai/answers/mcp-tool-reliability/whats-the-difference-between-mcp-and-a-plain-api-call
More on Mcp tool reliability: https://tessary.ai/answers/mcp-tool-reliability
From Tessary, agent reliability for AI agents in production: https://tessary.ai