add message type

Author: aksheyd

src/mcp/client/session.py

@@ -163,7 +163,11 @@ async def send_ping(self) -> types.EmptyResult:
         )
 
     async def send_progress_notification(
-        self, progress_token: str | int, progress: float, total: float | None = None
+        self,
+        progress_token: str | int,
+        progress: float,
+        total: float | None = None,
+        message: str | None = None,
     ) -> None:
         """Send a progress notification."""
         await self.send_notification(
@@ -174,6 +178,7 @@ async def send_progress_notification(
                         progressToken=progress_token,
                         progress=progress,
                         total=total,
+                        message=message,
                     ),
                 ),
             )

src/mcp/server/session.py

@@ -261,7 +261,11 @@ async def send_ping(self) -> types.EmptyResult:
         )
 
     async def send_progress_notification(
-        self, progress_token: str | int, progress: float, total: float | None = None
+        self,
+        progress_token: str | int,
+        progress: float,
+        total: float | None = None,
+        message: str | None = None,
     ) -> None:
         """Send a progress notification."""
         await self.send_notification(
@@ -272,6 +276,7 @@ async def send_progress_notification(
                         progressToken=progress_token,
                         progress=progress,
                         total=total,
+                        message=message,
                     ),
                 )
             )

src/mcp/shared/progress.py

@@ -42,12 +42,13 @@ class ProgressContext(
     progress_token: ProgressToken
     total: float | None
     current: float = field(default=0.0, init=False)
+    message: str | None
 
     async def progress(self, amount: float) -> None:
         self.current += amount
 
         await self.session.send_progress_notification(
-            self.progress_token, self.current, total=self.total
+            self.progress_token, self.current, total=self.total, message=self.message
         )
 
 
@@ -77,7 +78,7 @@ def progress(
     if ctx.meta is None or ctx.meta.progressToken is None:
         raise ValueError("No progress token provided")
 
-    progress_ctx = ProgressContext(ctx.session, ctx.meta.progressToken, total)
+    progress_ctx = ProgressContext(ctx.session, ctx.meta.progressToken, total, None)
     try:
         yield progress_ctx
     finally:

src/mcp/shared/session.py

@@ -377,7 +377,11 @@ async def _received_notification(self, notification: ReceiveNotificationT) -> No
         """
 
     async def send_progress_notification(
-        self, progress_token: str | int, progress: float, total: float | None = None
+        self,
+        progress_token: str | int,
+        progress: float,
+        total: float | None = None,
+        message: str | None = None,
     ) -> None:
         """
         Sends a progress notification for a request that is currently being

src/mcp/types.py

@@ -337,6 +337,11 @@ class ProgressNotificationParams(NotificationParams):
     total is unknown.
     """
     total: float | None = None
+    """
+    Message related to progress. This should provide relevant human readble 
+    progress information.
+    """
+    message: str | None = None
     """Total number of items to process (or total progress required), if known."""
     model_config = ConfigDict(extra="allow")