Is your MCP server ready for the 2026-07-28 spec?

The 2026-07-28 revision is current. The largest version bump since MCP launched: the initialize handshake is removed, Mcp-Session-Id is eliminated, and new routing headers are mandatory. Nearly every remote server we probe is still on an older revision. Paste your endpoint (or GitHub repo) and we'll test it live: read-only, no credentials, results in seconds.

What this checks

Session dependence (SEP-2567): Mcp-Session-Id is removed. Servers that require it break behind stateless clients and plain load balancers.
Handshake dependence (SEP-2575): initialize is removed. Clients call server/discover instead and send client info in _meta on every request.
Protocol version: what your server negotiates today.
Deprecated capabilities: logging (plus roots and sampling client-side) is now in a 12-month removal window.
OAuth discovery: protected-resource metadata for auth-gated servers.
SDK version bounds (repo mode): the breaking SDK major has shipped, and unbounded mcp dependencies resolve to it on the next install.

Checks are read-only: one handshake, one tools/list, one server/discover call, and public metadata fetches. We never invoke tools or send credentials. Details in the methodology.