Session Handoff [python-contract]: Mypy-Only Build Directories Settled and Released as 2.0.737

[ptr727]

This round finished #1941 with the maintainer's decision. A build-profile Python directory may use mypy as its only CI type checker, and whichever checker CI runs is held to strict. The change landed in #2005 and #2007, promoted in #2006, and was released as 2.0.737.

Next steps, in priority order

Re-read each issue rather than trusting these summaries.

1. PlexCleaner adopts the gate. This happens in PlexCleaner's own session and is unchanged from earlier links. It is first in the adoption order the maintainer set on Gate Every Repository's Python on Its Code, Not on Its Config #1800. Pin the validator to 2.0.737 or later and pass python-directories: RegressionTests on both callers. RegressionTests/ needs a tests/ suite and a mypy config first, and that config now owes mypy's strict flags if mypy is its only CI checker (python.pyright.config). Done looks like: CI is green and the (python.directories.declared) driftNote is deleted.
2. Name the Mypy Suppression Mechanisms Beside Pyright's in python-codestyle #2004: name the mypy suppression mechanisms ([[tool.mypy.overrides]], # type: ignore[code]) beside the pyright ones in python-codestyle. This touches the same SKILL.md the auto-1947 lane is editing, so check that lane's state first.
3. Remaining deferred edge cases: Read a with: Input Past a Deeper-Indented Comment in the Audit #1916 and Count a setup.cfg [mypy] Section as a Declared Directory's Type Checker #1915, then configure.sh Resolves a Registry Entry by Name Rather Than by owner/repo Identity #1894 and Three Test Harnesses Build a Stand-In PATH With an Empty Fallback When PATH Is Unset #1862.

External blockers

• Each adoption runs in another repository's session.

Internal dependencies

• Name the Mypy Suppression Mechanisms Beside Pyright's in python-codestyle #2004 edits .agents/skills/python-codestyle/SKILL.md near the type-checking paragraph. The auto-1947 lane (handoff Session Handoff [auto-1947]: State the Python Build Profile by Its Trait, Not One of Its Forms #1981) has an unmerged branch rewriting that file's profile and local-loop sections. Land Name the Mypy Suppression Mechanisms Beside Pyright's in python-codestyle #2004 after that lane merges, or coordinate the rebase.
• Count a setup.cfg [mypy] Section as a Declared Directory's Type Checker #1915 (count a setup.cfg [mypy] section as a declared directory's checker) now sits beside python.config.placement, which calls a standalone mypy config drift outside a Home Assistant integration. Re-read both before starting it.

State

Re-derive each of these at resume.

• main: carries Allow Mypy Strict as a Build Directory's Only Type Checker #2005 and Group the Mypy Option's Clauses So It Reads One Way #2007 through promotion Promote develop to main: Allow Mypy Strict as a Build Directory's Only Type Checker #2006, released as 2.0.737.
• develop: at Group the Mypy Option's Clauses So It Reads One Way #2007's squash commit, level with main's content.
• Open PRs: none from this track.
• Worktrees: this round's two worktrees and their branches are removed, locally and on the remote. The base clone is on develop and clean. This machine's skills are refreshed from main at the release.
• Other tracks: default (Session Handoff [default]: Audit Report Authorship Settled, Unattended Loop Live-Tested, 2.0.680 Released #1828), plus the auto-* lanes.

The parked decision queue

No open issue carries decision. Both questions this round raised were asked and answered in-session: mypy strict for a mypy-only build directory, and fixing one more open finding after the review budget ran out.

What the last round did

• Allow Mypy Strict as a Build Directory's Only Type Checker #2005: relaxed python.pyright.config and python.mypy.allowed to allow mypy-only, held each CI checker to strict, named mypy's standalone configs in python.config.placement, and stated the same rule in AUDIT.md, README.md, and the python-codestyle skill.
• Group the Mypy Option's Clauses So It Reads One Way #2007: grouped the mypy option's clauses after promotion review found them ambiguous.
• Declined on Promote develop to main: Allow Mypy Strict as a Build Directory's Only Type Checker #2006: the local-loop block's uv run pyright line. That line predates this change, and the paragraph after it names uv run mypy src.
• Filed Name the Mypy Suppression Mechanisms Beside Pyright's in python-codestyle #2004, a pre-existing gap the local review found.

What not to repeat

• Missing a surface that states the rule. The first diff edited the spec alone. Local review then found the skill, README.md, and finally AUDIT.md each still stating the old rule, one round per surface. Grep every surface for the rule's claim, AUDIT.md included, before the first push.
• Writing a strictness demand without its profile scope. The first AUDIT.md wording demanded strict of lint-only directories too, which the spec does not. Copy the scope from the spec rule (minProfile) along with its text.
• Naming strict = true for mypy. That key is global, so a test tree can't be relaxed with it the way pyright's path-scoped strict = ["src"] allows. Say "mypy's strict flags".
• Scripted multi-line replacements ending mid-line. Twice, an old string that stopped before the end of a source line glued the rest of that line onto the new text's last line. End a replaced span at a newline.

New learnings

None beyond the entries above, which describe this round's attempts rather than general lessons.

[ptr727]

Continued in #2014, round 8 on track python-contract.