Title: Add py.typed so package is recognized as typed (PEP 561)

[DarkDk123]

Summary

langchain-mcp-adapters seems to have type-hints, but isn’t recognized as typed by mypy because it lacks a py.typed marker (PEP 561).

Steps to reproduce

uv pip install mypy langchain-mcp-adapters --system
uv run mypy -c "from langchain_mcp_adapters.client import MultiServerMCPClient"

Output:

uv run mypy -c "from langchain_mcp_adapters.client import MultiServerMCPClient"
<string>:1: error: Skipping analyzing "langchain_mcp_adapters.client": module is installed, but missing library stubs or py.typed marker  [import-untyped]
<string>:1: note: See https://mypy.readthedocs.io/en/stable/running_mypy.html#missing-imports
Found 1 error in 1 file (checked 1 source file)
[ble: exit 1]

IMG:

Expected

If built with proper type-hints :

No “missing library stubs” error — mypy should use the inline hints.

Fix

1. Add an empty py.typed file inside langchain_mcp_adapters/.
2. Include it in the build:

[tool.setuptools.package-data]
"langchain_mcp_adapters" = ["py.typed"]

Should i release a PR, so mypy will recognize the types ?

[Tomodo1773]

I saw this issue and noticed someone asked about opening a PR,
but since there hasn’t been a maintainer response yet,
I can prepare a small PR adding the py.typed marker if that helps.

[DarkDk123]

I saw this issue and noticed someone asked about opening a PR, but since there hasn’t been a maintainer response yet, I can prepare a small PR adding the py.typed marker if that helps.

Yes @Tomodo1773, You can prepare a PR, but without maintainer activity/affirmation, i'm waiting for it.