Rust code ok, 4 items to address:

1. Remove specs/ — 533 lines of process docs (spec, plan, tasks, research, checklists). Should not be in the repo.
2. Clean CLAUDE.md — remove the "Active Technologies" and "Recent Changes" sections added at the bottom. Keep only the module table entry.
3. Duplicate rtk lint mypy — already merged in feat(python): add lint dispatcher + universal format command #100. Either remove the duplicate parser in lint_cmd.rs or have it delegate to mypy_cmd.
4. Rebase needed — mergeStateStatus: UNSTABLE.

Thanks for the mypy support — this fits well in the Python tooling story alongside ruff/pytest/pip.

The PR has a merge conflict with master — could you rebase? A lot has changed since Feb 13 (Python/Go support landed in 0.18.0).

Once rebased, I'll do a proper review. The approach (grouped errors by file, top error codes summary) looks solid from the description.

Addressed all 4 review items:

1. Removed specs/ -- deleted all 5 process doc files (spec, plan, tasks, research, checklists)
2. Cleaned CLAUDE.md -- removed "Active Technologies" and "Recent Changes" sections; kept only the mypy module table entry
3. Deduplicated mypy handler -- made mypy_cmd::filter_mypy_output() public and lint_cmd.rs now delegates to it (removed 145 lines of duplicate code + 2 redundant tests). The mypy_cmd version is more capable: handles column numbers, note continuations, file-less errors, and shows full error details
4. Rebased on master (c29644b, v0.21.1)

All 387 tests pass, including 11 mypy-specific tests. Zero new clippy warnings.

@FlorianBruniaux All 4 review items have been addressed (see previous comment for details). Could you remove the awaiting-changes label and merge when ready? Thanks!

Clean implementation. lazy_static! for regex, exit code preserved, python3 -m mypy fallback, no production unwrap().

Minor: which_command() duplicates an existing helper in utils.rs. Could use crate::utils::tool_exists() instead, but not a blocker.

LGTM.