Application Programming Interface (API)

An Application Programming Interface (API) is a set of protocols and definitions that allow different software applications to communicate and exchange data.

Role in AI & Large Language Models

  • External Interaction: APIs are essential for large-language-models (LLMs) to interact with external data sources, services, and computational tools.
  • Tool Use: They provide the primary mechanism for agentic-ai to extend their capabilities beyond their static training data.

Emerging Standards

  • model-context-protocol (MCP) vs. API:
    • While APIs are the traditional method for facilitating external interaction, MCP is an emerging protocol designed specifically for the context-sharing needs of LLMs.
    • Both frameworks aim to bridge the gap between models and external data, but they differ in their approach to handling context and tool integration.
  • 2026 04 14 MCP vs API for LLM by IBM

Source Notes