# MCP vs API: How they work together and when to use each

DevFeed: [MCP vs API: How they work together and when to use each](<https://devfeed.tech/articles/mcp-vs-api-how-they-work-together-and-when-to-use-each-13353.md>)

Original publisher: [Read original article](<https://circleci.com/blog/mcp-vs-api/>)

Author: Jacob Schmitt

Published: 2026-08-20T21:30:00Z

Content type: tutorial

Language: en

Sources: [The CircleCI Blog Feed | CircleCI](<https://devfeed.tech/sources/the-circleci-blog-feed-circleci.md>)

Topics: [Model Context Protocol (MCP)](<https://devfeed.tech/topics/model-context-protocol-mcp.md>), [API](<https://devfeed.tech/topics/api.md>), [Artificial Intelligence](<https://devfeed.tech/topics/ai.md>)

Tags: [agents](<https://devfeed.tech/tags/agents.md>), [ai-development](<https://devfeed.tech/tags/ai-development.md>), [api](<https://devfeed.tech/tags/api.md>), [mcp](<https://devfeed.tech/tags/mcp.md>), [mcp-vs-api](<https://devfeed.tech/tags/mcp-vs-api.md>), [mcp-vs-rest](<https://devfeed.tech/tags/mcp-vs-rest.md>), [when-to-use-mcp-vs-api](<https://devfeed.tech/tags/when-to-use-mcp-vs-api.md>), [will-mcp-replace-apis](<https://devfeed.tech/tags/will-mcp-replace-apis.md>)

## AI overview

This tutorial explains how APIs and the Model Context Protocol differ and work together. APIs expose operations for software to call, while MCP provides a standardized way for AI applications to discover and invoke selected capabilities at runtime, often through existing REST, GraphQL, or RPC interfaces.

## Source excerpt

An API exposes operations software can call. MCP lets AI agents discover and invoke them at runtime. Learn how the two work together, and when to use each.