fix(mcp): add uvx PATH preflight check and actionable guidance (#5600)

[shivakumar777-web]

Closes #5600

Summary of Changes

• Added Windows %LOCALAPPDATA%\Programs\uv\bin\ and standard \uv\ installation fallback directories to \�ersion_manager_dirs()\ in \spawn_env.rs.
• Added unit test \initialize_missing_uvx_mentions_uv_and_docs_link\ in \stdio.rs\ verifying that missing \uvx\ produces actionable installation guidance pointing to \https://docs.astral.sh/uv/\.

Verification

• \cargo test --manifest-path Cargo.toml --lib openhuman::mcp::config_servers::stdio\ (passed)
• \cargo check --manifest-path Cargo.toml\ (passed)

Summary by CodeRabbit

• Bug Fixes
  • Improved Windows command resolution by recognizing commonly used local application directories.
  • Enhanced error messages when an uvx-based connection cannot start, including guidance for installing uv (Python) and a link to official documentation.

[tinysweeper]

tinysweeper found nothing blocking. Approving.

$0.0000 · 0 in / 0 out · 120 embedded · openrouter/openai/text-embedding-3-small

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 07f99839-1a6f-4bb7-a0ae-8b8368e5a3d9

📥 Commits

Reviewing files that changed from the base of the PR and between 157a07a and 3d612e0.

📒 Files selected for processing (1)

• src/openhuman/mcp/config_servers/spawn_env.rs

🚧 Files skipped from review as they are similar to previous changes (1)

• src/openhuman/mcp/config_servers/spawn_env.rs

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📝 Walkthrough

Walkthrough

The Windows uv path fallback expression was reformatted. An async stdio test verifies actionable diagnostics when uvx is unavailable.

Changes

uvx resolution and diagnostics

Layer / File(s)	Summary
Windows PATH fallback formatting src/openhuman/mcp/config_servers/spawn_env.rs	The Windows uv path fallback call was reformatted. Directory discovery behavior is unchanged.
Missing uvx diagnostic validation src/openhuman/mcp/config_servers/stdio.rs	An async test verifies that missing uvx errors mention uv (Python) and the official uv documentation URL.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Merge Risk: ⚪ Minimal · up to 3d612

The change adds localized uvx PATH detection and actionable installation guidance, with the stated tests and checks passing; no actionable merge-blocking risk remains.

Poem

I check the path from hop to hop,
And test the message when tools stop.
If uvx is missing from the way,
Clear docs now guide the fix today.
— A careful rabbit 🐇

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly identifies the MCP change: an uvx PATH preflight check with actionable guidance.
Linked Issues check	✅ Passed	The changes address issue #5600 by checking uvx availability and testing actionable installation guidance for missing uv.
Out of Scope Changes check	✅ Passed	The path handling update and async test directly support the uvx preflight check and issue #5600.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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[M3gA-Mind]

Closing this — not because the idea is wrong, but because the code it changes no longer exists in this repository.

Both files this PR touches were removed when the MCP client was extracted into tinyhumansai/tinymcp (commit 050b2d687):

• src/openhuman/mcp/config_servers/spawn_env.rs — gone from main
• src/openhuman/mcp/config_servers/stdio.rs — gone from main

src/openhuman/mcp/config_servers/ is not present on main at all, which is why this shows as CONFLICTING/DIRTY: there is no longer a base to rebase onto. That happened after this PR was opened — it was written against an accurate tree at the time.

If you would like to carry the work forward, the equivalent code now lives in vendor/tinymcp/crates/tinymcp/src/lib.rs. A PR against tinyhumansai/tinymcp would reach openhuman through a submodule bump.

One thing worth flagging for whoever picks it up: this PR carries Closes #5600, and a preflight check would not actually close that issue. The reported failure there is that uv is not installed on the staging host — better error messaging makes the failure legible, it does not install the dependency. Those are two separate deliverables, so a future PR should reference the issue without a closing keyword.

#5600 remains open.