Package Exports

@aeye/core

Readme

@aeye/core

Core primitives for building AI agents, tools, and prompts with TypeScript. Provides a type-safe, composable framework for creating sophisticated AI applications with structured inputs/outputs, tool calling, and context management.

Features

🎯 Type-Safe Components - Prompts, Tools, and Agents with full TypeScript support
🔧 Tool Calling - Native support for function/tool calling with schema validation
📝 Template-Based Prompts - Handlebars templates for dynamic prompt generation
✅ Schema Validation - Zod integration for structured inputs and outputs
🌊 Streaming Support - First-class streaming for real-time AI responses
🔄 Composable Architecture - Tools can use other tools, prompts can use tools, agents orchestrate everything
📊 Context Management - Type-safe context threading and automatic token window management
🎛️ Flexible Execution - Sequential, parallel, or immediate tool execution modes

Installation

npm install @aeye/core zod handlebars

Core Concepts

Components

All AI primitives implement the Component interface:

Prompt - Generates AI responses with optional tool usage and structured outputs
Tool - Extends AI capabilities with custom functions and external integrations
Agent - Orchestrates complex workflows combining prompts and tools

Context & Metadata

Context (TContext) - Application-specific data threaded through operations (user, db, etc.)
Metadata (TMetadata) - Execution settings for AI requests (model, temperature, etc.)

Quick Start

Basic Prompt

import { Prompt } from '@aeye/core';
import z from 'zod';

const summarizer = new Prompt({
  name: 'summarize',
  description: 'Summarizes text concisely',
  content: 'Summarize the following text:\n\n{{text}}',
  
  // Transform input
  input: (input: { text: string }) => ({ text: input.text }),
  
  // Define output schema
  schema: z.object({
    summary: z.string().describe('A concise summary'),
    keyPoints: z.array(z.string()).describe('Main points')
  })
});

// Execute with a context that has an executor
const result = await summarizer.get(
  'result',
  { text: 'Long article text...' },
  {
    execute: yourAIExecutor, // Executor function from a provider
    messages: []
  }
);

console.log(result.summary);
console.log(result.keyPoints);

Creating Tools

import { Tool } from '@aeye/core';
import z from 'zod';

const weatherTool = new Tool({
  name: 'getWeather',
  description: 'Get current weather for a location',
  instructions: 'Use this tool to get weather data',
  
  schema: z.object({
    location: z.string().describe('City name or coordinates'),
    units: z.enum(['celsius', 'fahrenheit']).default('celsius')
  }),
  
  call: async (input, refs, ctx) => {
    const response = await fetch(
      `https://api.weather.com/v1/${input.location}`
    );
    const data = await response.json();
    
    return {
      temperature: data.temp,
      condition: data.condition,
      humidity: data.humidity
    };
  }
});

Prompts with Tools

const travelAdvisor = new Prompt({
  name: 'travelAdvisor',
  description: 'Provides travel advice based on weather',
  content: `You are a travel advisor. Help plan a trip to {{destination}}.
  
Use the weather tool to check current conditions, then provide:
- What to pack
- Activities to do
- Best times to visit`,
  
  input: (input: { destination: string }) => ({ 
    destination: input.destination 
  }),
  
  tools: [weatherTool],
  
  schema: z.object({
    recommendations: z.array(z.string()),
    packingList: z.array(z.string()),
    weatherNotes: z.string()
  })
});

// The AI will automatically call weatherTool if needed
const advice = await travelAdvisor.get(
  'result',
  { destination: 'Paris' },
  { execute: yourAIExecutor, messages: [] }
);

Streaming Responses

// Stream content only
for await (const chunk of summarizer.get(
  'streamContent',
  { text: 'Long text...' },
  { stream: yourAIStreamer, messages: [] }
)) {
  process.stdout.write(chunk);
}

// Stream all events (including tool calls)
for await (const event of summarizer.get(
  'stream',
  { text: 'Long text...' },
  { stream: yourAIStreamer, messages: [] }
)) {
  if (event.type === 'textPartial') {
    console.log('Text:', event.content);
  } else if (event.type === 'toolStart') {
    console.log('Tool started:', event.tool.name);
  } else if (event.type === 'toolOutput') {
    console.log('Tool result:', event.result);
  }
}

Building Agents

import { Agent } from '@aeye/core';

const researchAgent = new Agent({
  name: 'researcher',
  description: 'Conducts research on topics',
  
  refs: [searchTool, summarizeTool, analyzeTool],
  
  call: async (input: { topic: string }, [search, summarize, analyze], ctx) => {
    // Step 1: Search for information
    const searchResults = await search.run(
      { query: input.topic, limit: 5 },
      ctx
    );
    
    // Step 2: Summarize findings
    const summaries = [];
    for (const result of searchResults) {
      const summary = await summarize.get(
        'result',
        { text: result.content },
        ctx
      );
      summaries.push(summary);
    }
    
    // Step 3: Analyze and synthesize
    const analysis = await analyze.get(
      'result',
      { topic: input.topic, sources: summaries },
      ctx
    );
    
    return analysis;
  }
});

const research = await researchAgent.run(
  { topic: 'Quantum Computing' },
  { execute: yourAIExecutor, messages: [] }
);

Prompt Modes

The get method supports different execution modes:

Mode	Description	Returns
`'result'`	Get final structured output	`TOutput`
`'tools'`	Get tool call results	`PromptToolOutput[]`
`'stream'`	Stream all events	`AsyncGenerator<PromptEvent>`
`'streamTools'`	Stream tool outputs	`AsyncGenerator<PromptToolOutput>`
`'streamContent'`	Stream text content only	`AsyncGenerator<string>`

// Get structured result
const result = await prompt.get('result', input, ctx);

// Get tool outputs only
const tools = await prompt.get('tools', input, ctx);

// Stream everything
for await (const event of prompt.get('stream', input, ctx)) {
  // Handle different event types
}

Tool Execution Modes

Control how tools are executed:

const prompt = new Prompt({
  name: 'multi-tool',
  description: 'Uses multiple tools',
  content: 'Analyze the data',
  tools: [tool1, tool2, tool3],
  
  // Tool execution mode
  toolExecution: 'parallel', // 'sequential' | 'parallel' | 'immediate'
  
  // Retry configuration
  toolRetries: 2,         // Retry failed tools
  toolIterations: 3,      // Max iterations for tool calls
  toolsMax: 5,           // Max total tool calls
});

sequential - Wait for each tool to finish before continuing
parallel - Start all tools at once, wait for all to complete
immediate - Start tools immediately as they're available

Advanced Features

Context-Aware Tools

const contextTool = new Tool({
  name: 'contextAware',
  description: 'A context-aware tool',
  instructions: 'Use this tool...',
  
  // Schema can depend on context
  schema: (ctx) => {
    if (ctx.userRole === 'admin') {
      return z.object({
        action: z.enum(['read', 'write', 'delete'])
      });
    }
    return z.object({
      action: z.enum(['read'])
    });
  },
  
  // Check if tool is applicable
  applicable: (ctx) => {
    return ctx.isAuthenticated === true;
  },
  
  call: async (input, refs, ctx) => {
    // Implementation with context access
  }
});

Custom Validation

const validatedTool = new Tool({
  name: 'placeOrder',
  description: 'Place an order',
  
  schema: z.object({
    itemId: z.string(),
    quantity: z.number().min(1)
  }),
  
  // Additional validation beyond schema
  validate: async (input, ctx) => {
    const inventory = await checkInventory(input.itemId);
    if (inventory < input.quantity) {
      throw new Error(`Only ${inventory} items available`);
    }
  },
  
  call: async (input, refs, ctx) => {
    // Place order
  }
});

Event Tracking

import { withEvents } from '@aeye/core';

const runner = withEvents({
  onStatus: (instance) => {
    console.log(`${instance.component.name}: ${instance.status}`);
    if (instance.status === 'completed') {
      const duration = instance.completed - instance.started;
      console.log(`Took ${duration}ms`);
    }
  },
  
  onPromptEvent: (instance, event) => {
    if (event.type === 'usage') {
      console.log('Tokens used:', event.usage);
    }
  }
});

const result = await prompt.get(
  'result',
  { text: 'Hello' },
  {
    execute: yourAIExecutor,
    messages: [],
    runner
  }
);

Token Management

Automatic conversation trimming when token limits are reached:

const context = {
  execute: yourAIExecutor,
  messages: conversationHistory,
  
  // Token configuration
  defaultCompletionTokens: 2048,
  
  // Custom token estimation
  estimateTokens: (message) => {
    return message.content.length / 4; // Rough estimate
  }
};

// Prompt will automatically trim messages if needed
const result = await prompt.get('result', { text: 'Query' }, context);

Dynamic Reconfiguration

const adaptivePrompt = new Prompt({
  name: 'adaptive',
  description: 'Adapts based on execution stats',
  content: 'Solve: {{problem}}',
  schema: z.object({ solution: z.string() }),
  
  // Adjust configuration during execution
  reconfig: (stats, ctx) => {
    // If tools are failing, change strategy
    if (stats.toolCallErrors > 3) {
      return {
        config: { toolsOneAtATime: true },
        maxIterations: 2
      };
    }
    return {};
  }
});

API Reference

Prompt

class Prompt<TContext, TMetadata, TName, TInput, TOutput, TTools>

Constructor Options:

name: string - Unique identifier
description: string - Purpose description
content: string - Handlebars template
input?: Function - Transform input for template
schema?: ZodType | Function - Output schema
config?: Partial<Request> | Function - AI request config
tools?: Tool[] - Available tools
toolExecution?: 'sequential' | 'parallel' | 'immediate'
toolRetries?: number - Retry failed tools
toolIterations?: number - Max tool call iterations
outputRetries?: number - Retry invalid outputs
metadata?: TMetadata - Execution metadata
validate?: Function - Post-validation hook
applicable?: Function - Applicability check

Methods:

get(input, mode, ctx) - Execute and retrieve output
run(input, ctx) - Execute with full streaming
applicable(ctx) - Check if prompt can run

Tool

class Tool<TContext, TMetadata, TName, TParams, TOutput, TRefs>

Constructor Options:

name: string - Unique identifier
description: string - Purpose description
instructions?: string - Handlebars usage instructions
schema: ZodType | Function - Input schema
refs?: Component[] - Referenced components
call: Function - Implementation
validate?: Function - Post-validation hook
applicable?: Function - Applicability check

Methods:

run(input, ctx) - Execute the tool
compile(ctx) - Generate tool definition for AI
parse(ctx, args) - Parse and validate arguments
applicable(ctx) - Check if tool can run

Agent

class Agent<TContext, TMetadata, TName, TInput, TOutput, TRefs>

Constructor Options:

name: string - Unique identifier
description: string - Purpose description
refs?: Component[] - Referenced components
call: Function - Implementation with refs
applicable?: Function - Applicability check

Methods:

run(input, ctx) - Execute the agent
applicable(ctx) - Check if agent can run

Context Structure

interface Context<TContext, TMetadata> {
  // Required: AI execution
  execute?: Executor<TContext, TMetadata>;
  stream?: Streamer<TContext, TMetadata>;
  
  // Messages
  messages: Message[];
  
  // Token management
  defaultCompletionTokens?: number;
  estimateTokens?: (message: Message) => number;
  
  // Execution control
  signal?: AbortSignal;
  runner?: Events;
  
  // User context (TContext) spreads here
  [key: string]: any;
}

Request Configuration

interface Request {
  messages: Message[];
  temperature?: number;      // 0-2
  topP?: number;            // 0-1
  maxTokens?: number;
  stop?: string | string[];
  tools?: ToolDefinition[];
  toolChoice?: 'auto' | 'required' | 'none' | { tool: string };
  responseFormat?: 'text' | 'json' | ResponseFormat;
  // ... more options
}

Best Practices

Type Safety - Use TypeScript generics for context and metadata
Schema Validation - Use Zod for robust input/output validation
Error Handling - Wrap component execution in try-catch blocks
Token Management - Provide estimateTokens for accurate trimming
Tool Organization - Group related tools in agents
Testing - Unit test tools and prompts independently
Documentation - Document template variables and schemas
Context Minimization - Pass only necessary data in context
Streaming - Use streaming for better UX with long responses
Validation - Use validate hooks for business logic validation

Examples

See the src/__tests__ directory for comprehensive examples:

prompt-core-features.test.ts - Basic prompt usage
prompt-streaming-tool-events.test.ts - Streaming and events
tool.test.ts - Tool creation and usage
agent.test.ts - Agent orchestration
context-propagation.test.ts - Context handling

TypeScript Support

Full type inference across component hierarchies:

// Types are automatically inferred
const prompt = new Prompt({
  name: 'example',
  schema: z.object({ result: z.string() })
  // ...
});

// TypeScript knows the output type
const output = await prompt.get({}); // { result: string }

// Tool parameters are type-safe
const tool = new Tool({
  name: 'math',
  schema: z.object({ a: z.number(), b: z.number() }),
  call: (input, refs, ctx) => {
    // input is typed as { a: number, b: number }
    return input.a + input.b;
  }
});

Contributing

Contributions are welcome! See the main @aeye repository for contribution guidelines.

JSPM

@aeye/core

Package Exports

Readme

@aeye/core

Features

Installation

Core Concepts

Components

Context & Metadata

Quick Start

Basic Prompt

Creating Tools

Prompts with Tools

Streaming Responses

Building Agents

Prompt Modes

Tool Execution Modes

Advanced Features

Context-Aware Tools

Custom Validation

Event Tracking

Token Management

Dynamic Reconfiguration

API Reference

Prompt

Tool

Agent

Context Structure

Request Configuration

Best Practices

Examples

TypeScript Support

Contributing

License

Links