ToolSDK.ai is a free TypeScript SDK and marketplace that accelerates building agentic AI applications by providing instant access to over 5,300+ MCP (Model Context Protocol) servers and composable tools with one line of code, enabling developers to wire up real-world workflows combining language models with external systems. The platform exposes a unified client for loading packaged MCP servers (e.g., search, email, CRM, task management, storage, analytics) and converting them into OpenAI-compatible tools, handling authentication, invocation, and result orchestration so assistants can call, compare, and act on live data from services like Gmail, Salesforce, Google Drive, ClickUp, Notion, Slack, GitHub, analytics platforms, and custom web search or automation endpoints. It includes example quick-start integrations, supports metadata and conditional logic in multi-step orchestrations, and makes scaling to parallel agents and complex pipelines straightforward.