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Agents can use middleware to process requests and responses - for logging, validation, or transformation.

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Quick Start

1

Simple Usage

import { Agent, Middleware } from 'praisonai';

const logger: Middleware = async (ctx, next) => {
  console.log('Input:', ctx.input);
  await next();
  console.log('Output:', ctx.output);
};

const agent = new Agent({
  instructions: 'You are helpful',
  middleware: [logger]
});
2

With Configuration

const validate: Middleware = async (ctx, next) => {
  if (ctx.input.length > 1000) {
    throw new Error('Input too long');
  }
  await next();
};

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User Interaction Flow

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Configuration Levels

// Level 1: Array - Middleware list
const agent = new Agent({
  middleware: [logger, validator]
});

// Level 2: Function - Simple middleware
const agent = new Agent({
  middleware: [
    async (ctx, next) => {
      console.log(ctx.input);
      await next();
    }
  ]
});

// Level 3: Instance - Full control
const agent = new Agent({
  middleware: [
    {
      name: 'logger',
      handler: loggerFn,
      order: 1
    },
    {
      name: 'cache',
      handler: cacheFn,
      order: 2
    }
  ]
});

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Common Uses

Use CaseDescription
LoggingTrack all requests/responses
ValidationCheck inputs before processing
TransformationModify data in transit
CachingCache frequent responses

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API Reference

HooksConfig

Hooks configuration (middleware pattern)

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Best Practices

Each middleware should do one thing well.
Middleware runs in order - put validation first.
Forgetting next() breaks the chain.

Hooks

Lifecycle hooks

Guardrails

Input validation