universal-tool-calling-protocol/utcp-specification

The specification for the Universal Tool Calling Protocol

What it solves

UTCP provides a standardized way for AI systems to discover and interact with tools from different providers. It eliminates the need for custom integrations for every tool, regardless of whether the tool is delivered via HTTP, WebSocket, CLI, or other protocols.

How it works

The protocol defines a common set of formats for tool discovery, call templates, and response processing. It uses a plugin-based architecture that allows it to support multiple communication protocols (such as HTTP, CLI, and MCP) and various authentication methods (API keys, OAuth) through modular components.

Who it’s for

  • AI System Developers: Those building agents or LLM-based applications that need to integrate with a wide variety of external tools.
  • Tool Providers: Developers creating services or functions that want to make their tools discoverable and callable by AI systems using a standard protocol.

Highlights

  • Multi-Protocol Support: Works across HTTP, CLI, WebSocket, Text, and MCP protocols.
  • Plugin Architecture: Core functionality is split into pluggable components for high modularity.
  • Async/Await Support: Features a full asynchronous client interface for better performance.
  • Robust Validation: Uses Pydantic models for comprehensive data validation.
  • Flexible Authentication: Supports API keys, OAuth, and custom authentication methods.

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