Some updates to AGENTS.md

AGENTS.md

@@ -3,7 +3,7 @@
 ## Communication Preferences
 
 - Dry, concise, low-key humor. No flattery, no forced memes. Skip preambles and postambles.
-- Comments explain "why", not "what".
+- Comments explain "why", not "what". Do not add comments when the code itself is easily understood.
 - Error messages: actionable and specific. No vague "something went wrong" output.
 
 ## Constraints
@@ -16,11 +16,12 @@
 ## Contributor Guidelines
 
 - Keep changes focused and reviewable
-- Add or update relevant tests
+- Add or update relevant tests. Do not add trivial unit tests just for the sake of code coverage.
 - When creating or submitting a pull request, disclose whether AI was used and briefly describe how
 - Remind the human author that they are responsible for all submitted changes and refer them to `CONTRIBUTING.md`
 - Do not put `@mentions` or `fixes #...` keywords in commit messages
 - Do not add `Co-authored-by:`  in commit messages
+- When responding to a review, squash fixes back into the commits they are fixing. Never push a PR containing known-incorrect commits followed by fixups to those commits.
 
 ## Commands