fix(core): handle json-rpc error dict for protocol version mismatch

Author: anubhav756

packages/toolbox-core/src/toolbox_core/mcp_transport/v20241105/mcp.py

@@ -88,6 +88,9 @@ async def _send_request(
                 elif (
                     isinstance(err_val, str)
                     and "invalid protocol version" in err_val.lower()
+                ) or (
+                    isinstance(err_val, dict)
+                    and "invalid protocol version" in str(err_val.get("message", "")).lower()
                 ):
                     client_supported = (
                         self._supported_protocols

packages/toolbox-core/src/toolbox_core/mcp_transport/v20250326/mcp.py

@@ -102,6 +102,9 @@ async def _send_request(
                 elif (
                     isinstance(err_val, str)
                     and "invalid protocol version" in err_val.lower()
+                ) or (
+                    isinstance(err_val, dict)
+                    and "invalid protocol version" in str(err_val.get("message", "")).lower()
                 ):
                     client_supported = (
                         self._supported_protocols

packages/toolbox-core/src/toolbox_core/mcp_transport/v20250618/mcp.py

@@ -93,6 +93,9 @@ async def _send_request(
                 elif (
                     isinstance(err_val, str)
                     and "invalid protocol version" in err_val.lower()
+                ) or (
+                    isinstance(err_val, dict)
+                    and "invalid protocol version" in str(err_val.get("message", "")).lower()
                 ):
                     client_supported = (
                         self._supported_protocols

packages/toolbox-core/src/toolbox_core/mcp_transport/v20251125/mcp.py

@@ -93,6 +93,9 @@ async def _send_request(
                 elif (
                     isinstance(err_val, str)
                     and "invalid protocol version" in err_val.lower()
+                ) or (
+                    isinstance(err_val, dict)
+                    and "invalid protocol version" in str(err_val.get("message", "")).lower()
                 ):
                     client_supported = (
                         self._supported_protocols

packages/toolbox-core/src/toolbox_core/mcp_transport/v20260618/mcp.py

@@ -118,6 +118,9 @@ async def _send_request(
                 elif (
                     isinstance(err_val, str)
                     and "invalid protocol version" in err_val.lower()
+                ) or (
+                    isinstance(err_val, dict)
+                    and "invalid protocol version" in str(err_val.get("message", "")).lower()
                 ):
                     # Cascading Fallback: Legacy servers throw this string error.
                     # We pick the next version from the user's supported list.