FluidTools:

AI-powered API multi-tool agent with multi-provider support (OpenAI, Anthropic, Ollama, Gemini, Nebius)

Available on NPM and GitHub

Overview

FluidTools is a powerful NPM package that transforms REST API collections (Postman 2.1 JSON format) into intelligent AI agent tools. Built with TypeScript, it integrates seamlessly into any Node.js/TypeScript server, enabling you to quickly add AI agents that can interact with your APIs using natural language queries.

Key Features

• 🚀 One-Click Tool Generation: Convert Postman collections to LangChain-compatible tools instantly
• 🤖 Multi-Provider AI Support: Compatible with OpenAI, Anthropic, Ollama, Gemini, and Nebius
• 🔧 LangGraph Integration: Robust agent orchestration with state management and memory
• 📊 Semantic Tool Selection: Optional embedding-based tool filtering for large APIs
• ✅ Human-in-Loop Security: Exact tool selection and user approval for sensitive operations
• 🌍 Multi-Language Support: Babel integration for international chatbot deployment
• 🌐 Server Agnostic: Integrates with any Express/Fastify/Koa server
• ⚡ TypeScript First: Full type safety with Zod schemas

Sponsors

Installation

npm install fluidtools

Quick Start

1. Convert Postman Collection to Tools

npx fluidtools ./api.json ./tools.ts

Or programmatically:

import { postmanToLangChainCode } from "fluidtools";

const collection = JSON.parse(fs.readFileSync("./api.json", "utf-8"));
const code = postmanToLangChainCode(collection);
fs.writeFileSync("./tools.ts", code);

2. Create AI Agent Server

import express from "express";
import { FluidToolsClient, loadProviderConfigFromEnv } from "fluidtools";
import { generateTools } from "./tools.ts"; // Generated tools

const app = express();
app.use(express.json());

const providerConfig = loadProviderConfigFromEnv();
const fluidClient = new FluidToolsClient(
  providerConfig,
  generateTools,
  "You are a helpful API assistant.",
  10, // max tool calls
  true // debug mode
);

app.get("/", async (req, res) => {
  const { query } = req.query;
  const { authorization } = req.headers;

  const token = authorization?.split(" ")[1];
  const response = await fluidClient.query(query, token);

  res.send({ message: response });
});

app.listen(8000);

3. Query Your AI Agent

curl -X GET "http://localhost:8000/?query=Get user details and list their projects" \
  -H "Authorization: Bearer YOUR_TOKEN"

Architecture

System Architecture Diagram

graph TD
    A[Postman 2.1 JSON] --> B[CLI Tool<br/>fluidtools]
    B --> C[Tool Generation<br/>TypeScript + Zod Schemas]
    C --> D[FluidTools Client]

    D --> E[Optional Embedding Service<br/>Semantic Tool Selection]

    D --> F[System Prompt<br/>Custom Chatbots]
    F --> G[LangGraph Agent<br/>Orchestration & Memory]

    G --> H[Multi-Provider LLM Support]
    H --> I[Multiple Model Support]
    I --> J[Multi-Language Support<br/>Babel Integration]

    J --> K[Server Integration<br/>Express/Fastify/Koa]
    K --> L[API Exposed<br/>REST/WebSocket]

    subgraph "🔧 Tool Conversion Pipeline"
        A
        B
        C
    end

    subgraph "🤖 AI Agent Core"
        D
        F
        G
        H
        I
        J
    end

    subgraph "🌐 Integration Layer"
        K
        L
    end

    subgraph "⚡ Security & Control"
        M[Human-in-Loop<br/>Tool Confirmation]
        N[Exact Tool Selection<br/>Security Controls]
    end

    G --> M
    M --> N

    subgraph "Provider Ecosystem"
        O[OpenAI<br/>GPT-4, GPT-3.5]
        P[Anthropic<br/>Claude 3.5, Opus]
        Q[Ollama<br/>Local Models]
        R[Gemini<br/>2.5 Flash, Pro]
        S[Nebius<br/>Kimi-K2]
    end

    I --> O
    I --> P
    I --> Q
    I --> R
    I --> S

    L --> T[Chatbot UI<br/>Gradio/React/Web]

System Architecture Overview

1. Postman Collection Processing

   • Parses Postman 2.1 JSON format
   • Extracts requests, parameters, bodies, and schemas
   • Generates TypeScript tools with automatic Zod validation

2. Tool Generation Engine

   • Converts each API endpoint into a LangChain tool
   • Handles path variables, query parameters, headers
   • Supports all HTTP methods (GET, POST, PUT, DELETE, PATCH)
   • Auto-generates meaningful descriptions

3. Multi-Provider LLM Integration

   • Unified interface for different AI providers
   • Configurable model selection and API keys
   • Consistent response formatting

4. LangGraph Orchestration

   • Sequential tool execution with memory
   • State persistence using checkpointer
   • Built-in retry mechanisms and error handling

5. Optional Embedding Layer

   • Semantic indexing of tool definitions
   • Cosine similarity-based tool selection
   • Reduces token usage for large toolsets

6. Server Integration

   • Session-based conversation management
   • Tool call confirmation system
   • Rate limiting and authentication

Data Flow

Postman Collection JSON ──────┐
                              │
CLI Tool (fluidtools) ────────▼
                              │
TypeScript Tool Code ─────────▼
                              │
Express/Fastify Server ───────▼
                              │
FluidTools Client ────────────▼
                              │
LangGraph Agent ──────────────▼
                              │
LLM Provider + Tools ─────────▼
                              │
API Calls + Responses ────────▼
                              │
User-Friendly Chat Response ──▼

Demo 1: Gradio Integration (Public Testing)

Located in ./demo/server/, this demo provides a complete Express server with Gradio UI integration for testing your AI agents:

Features:

• Web upload interface for Postman collections
• Real-time chat with your AI agent
• Provider selection (OpenAI, Anthropic, etc.)
• Rate limiting for free tier testing
• Tool confirmation dialogs
• Session management

Backend Setup:

cd demo/server
npm install
npm start

Backend runs on http://localhost:3000

Frontend (Gradio UI):

cd demo/gradioServer
pip install -r requirements.txt
python app.py

Frontend runs on http://localhost:7860 - open this in your browser for the beautiful glassmorphic chat interface with drag-and-drop Postman collection upload and real-time AI chat.

Demo 2: Real-World Integration (Cloud API Example)

Located in ./demo2/backend/, this demo shows a production-ready integration with a cloud provider API:

Features:

• Pre-generated tools from Ace Cloud API
• Simplified server setup
• Custom system prompts
• Environment variable configuration
• Tool approval workflows

This demo converts a comprehensive cloud API (instances, volumes, networks, billing, etc.) into AI tools.

Backend Setup:

cd demo2/backend
npm install
npm run dev

Backend runs on http://localhost:8000

Frontend (React App):

cd demo2/frontend
npm install
npm run dev

Frontend runs on http://localhost:5173 - features a modern React chat interface with:

• 🎤 Voice input/output capabilities (STT/TTS)
• 📱 Responsive design with markdown rendering
• ✅ Tool approval dialogs for sensitive operations
• 🔄 Real-time message streaming
• 🎨 Beautiful UI with copy/retry functionality
• 🔧 Advanced chatbot features

The React app connects to the backend API to provide a complete user experience for interacting with your AI agent.

API Reference

FluidToolsClient

Main class for managing AI agents.

new FluidToolsClient(
  providerConfig: ProviderConfig,
  toolsGenerator: Function,
  systemInstructions?: string,
  maxToolCalls?: number,
  debug?: boolean,
  expireAfterSeconds?: number,
  confirmationConfig?: ToolConfirmationConfig,
  toolsConfig?: Record<string, any>,
  embeddingConfig?: EmbeddingConfig
)

Key Methods

• query(query: string, accessToken?: string): Execute natural language query
• clearThread(accessToken?: string): Clear conversation memory
• getPendingConfirmations(accessToken?: string): Check pending tool approvals
• approveToolCall(toolCallId: string, accessToken?: string): Approve pending tool
• rejectToolCall(toolCallId: string, accessToken?: string): Reject pending tool

Provider Configuration

// Environment Variables
OPENAI_API_KEY=sk-...
ANTHROPIC_API_KEY=sk-ant-...
OLLAMA_BASE_URL=http://localhost:11434

// Or programmatic
const config = {
  provider: "openai",
  model: "gpt-4",
  apiKey: process.env.OPENAI_API_KEY,
  temperature: 0.1
};

CLI Usage

Generate tools from Postman collection:

fluidtools <input-file> [output-file] [--help]

# Examples
fluidtools api.json tools.ts
fluidtools ./collections/my-api.json

Contributing

1. Fork the repository
2. Create feature branch: git checkout -b feature/amazing-feature
3. Commit changes: git commit -m 'Add amazing feature'
4. Push to branch: git push origin feature/amazing-feature
5. Open a Pull Request

License

ISC

Contributors

We'd like to thank all the amazing people who have contributed to FluidTools! 👥

• KartikJoshiUK - Creator & Lead Developer
• Jatin Godnani - Core Contributor

Support

• 📖 Documentation: GitHub Wiki
• 🐛 Issues: GitHub Issues
• 💬 Discussions: GitHub Discussions

Built with ❤️ for developers who want AI-powered API interactions