Time server fails under EDT timezone

[jamesfalkner]

Describe the bug
Running the Time server results in a failure due to local timezone moving to summer time ("EDT").

To Reproduce
Steps to reproduce the behavior:

1. Run uvx mcp-server-time while you are in the US/Eastern and/or America/New_York timezone while summer time ("EDT") is active.

Expected behavior
A working MCP server for time regardless of current timezone

Logs
Here's what I get when I run it:

➜  research git:(main) ✗ uvx mcp-server-time
Traceback (most recent call last):
  File "/Users/jhf/.pyenv/versions/3.11.9/lib/python3.11/zoneinfo/_common.py", line 12, in load_tzdata
    return resources.files(package_name).joinpath(resource_name).open("rb")
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jhf/.pyenv/versions/3.11.9/lib/python3.11/pathlib.py", line 1044, in open
    return io.open(self, mode, buffering, encoding, errors, newline)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: '/Users/jhf/.cache/uv/archive-v0/ZIoktJZ4w7sZkFWy-iTeK/lib/python3.11/site-packages/tzdata/zoneinfo/EDT'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/jhf/.cache/uv/archive-v0/ZIoktJZ4w7sZkFWy-iTeK/bin/mcp-server-time", line 12, in <module>
    sys.exit(main())
             ^^^^^^
  File "/Users/jhf/.cache/uv/archive-v0/ZIoktJZ4w7sZkFWy-iTeK/lib/python3.11/site-packages/mcp_server_time/__init__.py", line 15, in main
    asyncio.run(serve(args.local_timezone))
  File "/Users/jhf/.pyenv/versions/3.11.9/lib/python3.11/asyncio/runners.py", line 190, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/Users/jhf/.pyenv/versions/3.11.9/lib/python3.11/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jhf/.pyenv/versions/3.11.9/lib/python3.11/asyncio/base_events.py", line 654, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/Users/jhf/.cache/uv/archive-v0/ZIoktJZ4w7sZkFWy-iTeK/lib/python3.11/site-packages/mcp_server_time/server.py", line 119, in serve
    local_tz = str(get_local_tz(local_timezone))
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jhf/.cache/uv/archive-v0/ZIoktJZ4w7sZkFWy-iTeK/lib/python3.11/site-packages/mcp_server_time/server.py", line 45, in get_local_tz
    return ZoneInfo(str(tzinfo))
           ^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jhf/.pyenv/versions/3.11.9/lib/python3.11/zoneinfo/_common.py", line 24, in load_tzdata
    raise ZoneInfoNotFoundError(f"No time zone found with key {key}")
zoneinfo._common.ZoneInfoNotFoundError: 'No time zone found with key EDT'

Additional context
This only started failing yesterday (the first day of daylight savings time in the US). Prior to this it was working.

[mor10]

Same happens for PDT

[mileswangs]

same error in CST

[Roalkege]

Same for zoneinfo._common.ZoneInfoNotFoundError: 'No time zone found with key Mitteleuropäische Zeit'

[stronkfinkle]

& BST

[zstbee]

same error in CST
i have try to re-edit th settings developer config as this :
command:
python3
arguments:
-m mcp_server_time --local-timezone "Etc/GMT-1"

is still not work

[xpire]

Same issue with AEDT

[MovGP0]

I have the same issue (in CEST: W. Europe Summer Time; Windows 11):

uvx mcp-server-time

Installed 23 packages in 316ms
Traceback (most recent call last):
  File "~\AppData\Local\Programs\Python\Python311\Lib\zoneinfo\_common.py", line 12, in load_tzdata
    return resources.files(package_name).joinpath(resource_name).open("rb")
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "~\AppData\Local\Programs\Python\Python311\Lib\pathlib.py", line 1044, in open
    return io.open(self, mode, buffering, encoding, errors, newline)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Users\\Johann.Dirry\\AppData\\Local\\uv\\cache\\archive-v0\\hjDT43lT6gZ4WHUVnywKc\\Lib\\site-packages\\tzdata\\zoneinfo\\W. Europe Summer Time'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "~\AppData\Local\uv\cache\archive-v0\hjDT43lT6gZ4WHUVnywKc\Scripts\mcp-server-time.exe\__main__.py", line 10, in <module>
  File "~\AppData\Local\uv\cache\archive-v0\hjDT43lT6gZ4WHUVnywKc\Lib\site-packages\mcp_server_time\__init__.py", line 15, in main
    asyncio.run(serve(args.local_timezone))
  File "~\AppData\Local\Programs\Python\Python311\Lib\asyncio\runners.py", line 190, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "~\AppData\Local\Programs\Python\Python311\Lib\asyncio\runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "~\AppData\Local\Programs\Python\Python311\Lib\asyncio\base_events.py", line 654, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "~\AppData\Local\uv\cache\archive-v0\hjDT43lT6gZ4WHUVnywKc\Lib\site-packages\mcp_server_time\server.py", line 119, in serve
    local_tz = str(get_local_tz(local_timezone))
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "~\AppData\Local\uv\cache\archive-v0\hjDT43lT6gZ4WHUVnywKc\Lib\site-packages\mcp_server_time\server.py", line 45, in get_local_tz
    return ZoneInfo(str(tzinfo))
           ^^^^^^^^^^^^^^^^^^^^^
  File "~\AppData\Local\Programs\Python\Python311\Lib\zoneinfo\_common.py", line 24, in load_tzdata
    raise ZoneInfoNotFoundError(f"No time zone found with key {key}")
zoneinfo._common.ZoneInfoNotFoundError: 'No time zone found with key W. Europe Summer Time'

[bsdayo]

Same issue with China Standard Time.

ZoneInfoNotFoundError: 'No time zone found with key China Standard Time'

[danilop]

I gave a look at the code. It seems you need to use a valid IANA timezone name. For example, the correct timezone for British Summer Time (BST) would be 'Europe/London'. This works for me:

mcp_server_time --local-timezone "Europe/London"

[MovGP0]

It seems you need to use a valid IANA timezone name.

If no parameter is set, the current user system setting should be used.

[Muhammad-Hazimi-Yusri]

to add in to answer from @danilop,

this config works for me:

    "time": {
      "command": "uvx",
      "args": [
        "mcp-server-time",
        "--local-timezone",
        "Europe/London"
      ]
    }