[dotnet-port] Align fsskills nested discovery with .NET

[Michelle Clayton (michelle-clayton-work)]

Stop recursive skill root discovery once a SKILL.md is found so nested files remain part of the parent skill instead of becoming independent skill roots.

[Copilot]

Pull request overview

This PR updates the file-system skill discovery logic to match the .NET behavior by treating a directory containing SKILL.md as a terminal “skill root” (i.e., do not recursively discover nested skill roots beneath it). This prevents nested SKILL.md files from being interpreted as separate skills and instead keeps nested content logically under the parent skill root.

Changes:

• Stop recursive skill-root discovery once a SKILL.md is found in a directory.
• Add a unit test asserting that a nested SKILL.md under a skill root does not produce an additional discovered skill.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
agent/skills/fsskills/source.go	Adds an early return to halt further recursive discovery once a skill root is detected.
agent/skills/fsskills/source_test.go	Adds coverage ensuring nested SKILL.md does not create an independent skill.

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[github-actions]

Cross-repo parity review

The Go change in searchForSkills (stop recursing once a SKILL.md is found) correctly mirrors the .NET SearchDirectoriesForSkills behavior, which also returns immediately after appending the skill directory.

However, the Python equivalent — the inner _search closure in FileSkillsSource._discover_skill_directories — does not return after appending a discovered skill path:

def _search(directory: str, current_depth: int) -> None:
    dir_path = Path(directory)
    if (dir_path / SKILL_FILE_NAME).is_file():
        discovered.append(str(dir_path.absolute()))
        # ← no return; recursion continues into subdirectories
    if current_depth >= MAX_SEARCH_DEPTH:
        return
    for entry in entries:
        if entry.is_dir():
            _search(str(entry), current_depth + 1)

This means for a layout like:

skills/
  parent/
    SKILL.md
    child/
      SKILL.md

• .NET / Go (after this PR): only parent/ is registered as a skill root; child/ is absorbed as part of parent/'s content tree
• Python: both parent/ and child/ are registered as independent skills

This is a meaningful behavioral divergence for any user who authors nested SKILL.md trees and expects consistent cross-SDK behavior.

Suggested follow-up: open a tracking issue (or add a comment here) and align the Python implementation to add an early return after the discovered.append(...) call in _discover_skill_directories._search, matching .NET and Go semantics. The upstream file to change is:
python/packages/core/agent_framework/_skills.py → FileSkillsSource._discover_skill_directories inner _search function.

Generated by Go API Consistency Review Agent for issue #348 · 233.7 AIC · ⌖ 13 AIC · ⊞ 26.8K · ◷