Universal Tool Calling Protocol (UTCP) (www.utcp.io)

UTCP (Universal Tool Calling Protocol) is a lightweight, open standard that lets AI agents discover and call tools directly using their native protocols—no wrapper servers or middleman protocols required. Announced as an extension of OpenAPI (fully backward-compatible), UTCP provides agent-focused metadata (tags, average_response_size), multi-protocol call templates (HTTP, CLI, gRPC, MCP, SSE, text files) and explicit execution instructions so agents can invoke APIs with the same authentication and latency as human clients. The goal is simple: if a human can call your API, an AI agent should be able to call it too, using your existing security and scaling. Technically, UTCP exposes a “manual” (GET /utcp or converted from an OpenAPI spec) describing tools, inputs, call_template details and auth requirements; clients use modular protocol plugins (utcp-http, utcp-cli, utcp-mcp, etc.) to execute calls. Key benefits include zero proxy latency, native security, protocol flexibility and minimal maintenance. The v1.0 architecture is plugin-based (manuals, tools, call templates, client, repositories, search strategies), supports automatic OpenAPI→UTCP conversion, and targets both tool providers (SaaS, enterprises) and agent builders. UTCP aims to replace custom wrappers and MCP-style middlemen, easing integration, lowering operational overhead, and enabling faster, more secure tool-enabled agents.