Quick Example

MiddlewareChain

Compose multiple middleware into a reusable, ordered sequence.

MiddlewareChain groups middleware together so they can be managed as a single unit. Chains can be nested, combined with +, and modified dynamically.

Quick Example

from pydantic_ai_middleware import MiddlewareChain, MiddlewareAgent

# Create reusable middleware chains
security_chain = MiddlewareChain([
    AuthMiddleware(),
    RateLimitMiddleware(),
], name="security")

logging_chain = MiddlewareChain([
    RequestLogMiddleware(),
    ResponseLogMiddleware(),
], name="logging")

# Combine chains
full_chain = security_chain + logging_chain

# Or build incrementally
chain = MiddlewareChain(name="my-chain")
chain.add(AuthMiddleware())
chain.add(LoggingMiddleware())

# Use with an agent
agent = MiddlewareAgent(
    agent=base_agent,
    middleware=[full_chain],
)

API Reference

::: pydantic_ai_middleware.MiddlewareChain options: show_source: true members: - init - name - middleware - add - insert - remove - pop - replace - clear - copy - before_run - after_run - before_model_request - before_tool_call - after_tool_call - on_error