Many of us are still exploring the nooks and crannies of MCP and learning how to best use the building blocks of the protocol to enhance agents and applications. Some features, like Prompts, are frequently implemented and used within the MCP ecosystem. Others may appear a bit more obscure but have a lot of influence on how well an agent can interact with an MCP server. Server instructions fall in the latter category. ...
Release Timeline The next version of the Model Context Protocol specification will be released on November 25th, 2025, with a release candidate (RC) available on November 11th, 2025. We’re building in a 14-day RC validation window so client implementors and SDK maintainers can thoroughly test the protocol changes. This approach gives us the focused time we need to deliver critical improvements while applying our new governance model to the process. Summer Progress Our last spec was released on June 18, 2025, and focused on structured tool outputs, OAuth-based authorization, elicitation for server-initiated user interactions, and improved security best practices. ...
Today, we’re launching the Model Context Protocol (MCP) Registry—an open catalog and API for publicly available MCP servers to improve discoverability and implementation. By standardizing how servers are distributed and discovered, we’re expanding their reach while making it easier for clients to get connected. The MCP Registry is now available in preview. To get started: Add your server by following our guide on Adding Servers to the MCP Registry (for server maintainers) Access server data by following our guide on Accessing MCP Registry Data (for client maintainers) Single source of truth for MCP servers In March 2025, we shared that we wanted to build a central registry for the MCP ecosystem. Today we are announcing that we’ve launched https://registry.modelcontextprotocol.io as the official MCP Registry. As part of the MCP project, the MCP Registry, as well as a parent OpenAPI specification, are open source—allowing everyone to build a compatible sub-registry. ...
The official PHP SDK for the Model Context Protocol is now generally available. Built in collaboration with the PHP Foundation and Symfony, the PHP SDK handles protocol details, so developers don’t have to worry about low-level mechanics and can focus on building their applications. The initial release enables PHP developers to build MCP servers, exposing tools, prompts, and resources to AI applications. Support for PHP applications to act as MCP clients will follow. The PHP SDK now joins 9 other officially supported language SDKs in the MCP ecosystem, making it easier for developers everywhere to adopt MCP in their preferred language. ...
The Model Context Protocol (MCP) has adopted OAuth 2.1 as the foundation for its authorization framework. A key part of the authorization flow that MCP is particularly reliant on is client registration. This is especially important in a world where clients and servers don’t have a pre-existing relationship - we can’t assume that we will always know which MCP clients will connect to which MCP servers. This design highlights two challenges that need to be addressed: ...