Added & fixed some documentation

src/climbingboardgpt/paths.py

@@ -1,9 +1,16 @@
+"""Path discovery helpers for scripts that can be launched from any directory."""
 from __future__ import annotations
 
 from pathlib import Path
 
 
 def find_project_root(start: str | Path | None = None) -> Path:
+    """Walk upward until the repository root markers are found.
+
+    The project root is identified by both ``pyproject.toml`` and ``configs``.
+    If neither marker pair is found, the resolved starting directory is returned
+    so callers still have a deterministic base path.
+    """
     current = Path(start).resolve() if start is not None else Path.cwd().resolve()
     for candidate in [current, *current.parents]:
         if (candidate / "pyproject.toml").exists() and (candidate / "configs").exists():