SessionConfig

session/start’s reserved config object: no members in v1.

The protocol also ratifies “unknown keys are rejected, not ignored”. That is ruled and NOT exported: the protocol forbids it categorically and the conformance suite enforces that. The model carries the opt-in mechanism; this type does not opt in, so the published surface is unchanged.

Source

schema/msp/experimental/msp.schema.json#/types/SessionConfig

{
  "description": "`session/start`'s reserved `config` object: no members in\nv1.\n\nThe protocol also ratifies \"unknown keys are rejected, not ignored\". That is ruled and NOT exported: the protocol forbids it\ncategorically and the conformance suite enforces that. The model carries the opt-in\nmechanism; this type does not opt in, so the published surface is\nunchanged.",
  "properties": {},
  "type": "object"
}