What is an Agent Framework?

2 min read Updated

An agent framework is a software library that provides abstractions for building AI agents, handling concerns like tool management, state persistence, conversation flow, multi-agent coordination, and LLM integration.

WHY IT MATTERS

Building an AI agent from scratch means solving tool calling, state management, error handling, memory, and orchestration yourself. Agent frameworks handle these concerns so developers can focus on business logic.

The landscape has matured rapidly. LangGraph offers stateful graph-based agents. CrewAI specialises in multi-agent teams. OpenAI's Agents SDK provides a minimal, production-focused approach. PydanticAI emphasises type safety. Each makes different tradeoffs between flexibility and simplicity.

Critically, most major frameworks now support MCP natively — meaning they can connect to MCP servers (and MCP proxies like Intercept) out of the box. This decouples agent development from policy enforcement: build your agent in whatever framework you prefer, then add policy governance by pointing it at Intercept.

HOW POLICYLAYER USES THIS

Intercept works with any agent framework that supports MCP — which includes Claude Desktop, Cursor, Windsurf, VS Code Copilot, LangChain, OpenAI Agents SDK, PydanticAI, and more. Because Intercept is a transparent MCP proxy, no framework-specific plugin or SDK is needed. Point the framework's MCP client at Intercept, define your YAML policies, and tool calls are governed automatically.

FREQUENTLY ASKED QUESTIONS

Which agent frameworks work with Intercept?
Any framework with MCP client support: Claude Desktop, Cursor, Windsurf, VS Code Copilot, LangChain/LangGraph, OpenAI Agents SDK, PydanticAI, CrewAI, AutoGen, and others. If it speaks MCP, it works with Intercept.
Do I need a framework-specific plugin for Intercept?
No. Intercept is a transparent MCP proxy — it operates at the protocol level, not the framework level. You configure your framework's MCP client to connect to Intercept instead of the server directly. No plugin needed.
Do I need a framework to build an agent?
No. Many production agents are built with just an LLM API and a while loop. Frameworks help when you need state management, multi-agent coordination, or complex tool orchestration. Either way, Intercept enforces policies.

FURTHER READING

Enforce policies on every tool call

Intercept is the open-source MCP proxy that enforces YAML policies on AI agent tool calls. No code changes needed.

npx -y @policylayer/intercept
github.com/policylayer/intercept →
// GET IN TOUCH

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