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Fix bridge server crash with newer FastMCP versions #38

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Fix bridge server crash with newer FastMCP versions #38

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1a70065
Fix bridge server crash with newer FastMCP versions
SteffenPL Apr 8, 2026
d2693c6
Narrow exception handling and add debug logging
SteffenPL Apr 8, 2026
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12 changes: 11 additions & 1 deletion src/napari_mcp/bridge_server.py
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Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,8 @@
import asyncio
import logging
import threading

logger = logging.getLogger(__name__)
from concurrent.futures import Future
from concurrent.futures import TimeoutError as FutureTimeoutError
from typing import TYPE_CHECKING, Any
Expand Down Expand Up @@ -119,7 +121,15 @@ def __init__(self, viewer: napari.Viewer, port: int = 9999):
# Remove lifecycle tools that should not be available in bridge mode
# (the viewer is managed by napari, not the agent)
for name in ("close_viewer", "init_viewer"):
self.server._tool_manager._tools.pop(name, None)
try:
self.server.remove_tool(name)
except AttributeError:
try:
self.server._tool_manager._tools.pop(name, None)
except AttributeError:
logger.debug("Could not remove tool %r using any method", name)
except Exception as e:
logger.debug("remove_tool(%r) failed unexpectedly: %s", name, e)

# Override the 3 tools that differ in bridge mode
self._register_bridge_overrides()
Expand Down