Decide how to answer an HTTP GET to the MCP endpoint
(basic/transports §Listening for Messages from the Server): the server "MUST
either return Content-Type: text/event-stream in response to this HTTP GET,
or else return HTTP 405 Method Not Allowed".
Returns true when the GET should open a standalone server->client SSE stream,
false when it must be answered with 405. The standalone stream is offered for
the stable revisions (2025-03-26 / 2025-06-18 / 2025-11-25); on the draft,
which drops the standalone GET stream in favour of POST-response SSE, GET ->
405 is the correct answer.
Decide how to answer an HTTP GET to the MCP endpoint (basic/transports §Listening for Messages from the Server): the server "MUST either return Content-Type: text/event-stream in response to this HTTP GET, or else return HTTP 405 Method Not Allowed".
Returns true when the GET should open a standalone server->client SSE stream, false when it must be answered with 405. The standalone stream is offered for the stable revisions (2025-03-26 / 2025-06-18 / 2025-11-25); on the draft, which drops the standalone GET stream in favour of POST-response SSE, GET -> 405 is the correct answer.