AI-Native API Client

The API Client
Built for AI Agents

Name: Istek
Rating: 5 (100 reviews)
Author: Istek

Connect Claude, GPT, or any MCP-compatible AI to manage your APIs through natural language. Test HTTP, GraphQL, gRPC, WebSocket, and more in one native app.

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Istek AI-native API client interface showing MCP integration panel, HTTP request editor with response viewer, and AI agent connectivity — Istek AI-native application interface demonstrating MCP integration and API testing capabilities

Multi-Protocol Native

Not just REST. Native support for GraphQL, gRPC, MQTT, WebSocket, and Unix Sockets in one tool.

Privacy First

No accounts, no cloud sync, no tracking. Your data is encrypted locally and stays on your machine.

Rust Powered

Built with Rust and Tauri 2.0 for instant startup, low memory usage, and rock-solid stability.

MCP server connection panel in Istek showing Claude AI integration for API testing automation

AI assistant creating API requests through natural language commands in Istek

AI-Powered

MCP Integration for AI Agents

Connect your AI assistants directly to Istek. Let Claude, GPT, or any MCP-compatible agent manage your API collections, create requests, and run tests through natural language.

Create collections and requests via chat
8 built-in prompts for common workflows
Full API access for automation

Workflow

Environments & Variables

Switch between development, staging, and production with one click. Variables automatically resolve across all your requests, keeping your workflow clean and secure.

Global and environment-scoped variables
Secret variables with encryption
AWS, Azure, GCP secret provider integrations

Environment variable manager in Istek showing development, staging, and production environment configurations

Secret variables panel with encrypted API keys and cloud provider integrations for AWS, Azure, and GCP

Git Sync panel in Istek showing YAML collection export and repository connection settings

Two-way sync status showing collection changes being tracked and synced with Git repository

Collaboration

Git Sync for Teams

Store your collections as YAML files and sync them with Git. Version control your API definitions, review changes in PRs, and collaborate with your team seamlessly.

Human-readable YAML format
Two-way sync with auto-detection
Works with any Git provider

Quality

Test Runner for APIs

Write assertions for your API responses and run them as a suite. Validate status codes, response bodies, headers, and timing—all without leaving Istek.

JSONPath and regex assertions
Run entire collections at once
Detailed pass/fail reports

API Test Runner interface showing assertion editor with JSONPath queries and expected values configuration

Test results panel displaying passed and failed assertions with detailed response validation reports

Mock Server configuration panel in Istek with OpenAPI import and endpoint customization options

Running mock server showing generated fake data responses and configurable response delays

Development

Mock Server in Seconds

Generate a fully functional mock server from your OpenAPI spec with one click. Perfect for frontend development when the real API isn't ready yet.

Auto-generate from OpenAPI/Swagger
Realistic fake data generation
Custom response delays

All-in-One

8 Protocols, One Tool

Stop switching between tools. HTTP, WebSocket, GraphQL, gRPC, MQTT, Unix Socket, MCP, and SSE—all with native, first-class support in a single application.