compatibility

1 article tagged compatibility.

A single thin horizontal line with its middle section drawn in burnt orange, marking the revision boundary that splits MCP into two incompatible eras

MCP Backward Compatibility: What Still Talks to What

MCP revision 2026-07-28 removed the initialize handshake, so a new client cannot talk to an old server. Here is the full compatibility matrix and the probe that settles it.

mcp protocols10 min read