# AI Modification Log: x86_64 Config Comments

Date: 2026-06-29

## Summary

- Added purpose and maintenance comment headers to `Configs/x86_64-X`, `Configs/x86_64-Y`, and `Configs/x86_64-Z`.
- Added `NOTES_X86_CONFIG_OPTIMIZATION.md` with config-specific optimization todos.
- Updated the handoff and backlog notes to mark item #35 as completed.

## Behavior Impact

- No `CONFIG_*` selections were added, removed, or changed.
- The config comment update is documentation-only.

## Verification

- Inspected the config diff and confirmed the three config files only gained comment headers.
- Compared `CONFIG_*` lines against `HEAD` and confirmed no config selections changed.
- Checked line endings and confirmed X stayed LF, Y stayed LF without EOF newline, and Z stayed CRLF without EOF newline.
- Ran CRLF-aware whitespace validation before commit.