Model Context Protocol specification 2026-07-28, Key Changes

Publisher

Model Context Protocol project

URL

https://modelcontextprotocol.io/specification/2026-07-28/changelog

Published

2026-07-28

Updated

unknown

Accessed

2026-09-05

HTTP status

200

License

MIT license; permitted under the specification license

Source notes citing this source

• MCP revision 2026-07-28 replaced the Streamable HTTP GET endpoint and the resources/subscribe and resources/unsubscribe methods with subscriptions/listen, a single long-lived POST-response stream for opted-in server-to-client change notifications. in context
• MCP revision 2026-07-28 removed SSE stream resumability and message redelivery (the Last-Event-ID header and SSE event IDs) from Streamable HTTP; a broken response stream loses the in-flight request and clients MUST re-issue it as a new request with a new request ID. in context
• MCP revision 2026-07-28 removed protocol-level sessions and the Mcp-Session-Id header from the Streamable HTTP transport, and removed the initialize / notifications/initialized handshake so that every request carries its protocol version and client capabilities in _meta. in context
• The specification changelog announces a minimum 12 month deprecation window. disputed in context

Cite this source record

APA

WarmTransfer. (2026, July 28). Model Context Protocol specification 2026-07-28, Key Changes. WarmTransfer. https://warmtransfer.net/knowledge/sources/mcp-spec-2026-07-28-changelog

BibTeX

@misc{warmtransfer-mcp-spec-2026-07-28-changelog,
  title  = {Model Context Protocol specification 2026-07-28, Key Changes},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/mcp-spec-2026-07-28-changelog},
  note   = {Model Context Protocol project, accessed 2026-09-05}
}