checking-idioms-and-consistency

name	checking-idioms-and-consistency
description	Checks that a change follows the project's own conventions and the language/framework's idioms: formatter applied, idiomatic constructs over clumsy equivalents, recurring problems solved the same way the codebase already does, no second parallel way to do the same thing, consistent naming/casing/imports/file layout. Use when reviewing style, conventions, idioms, framework usage, or consistency with the rest of the codebase.
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checking-idioms-and-consistency

Does this look like the rest of the codebase? Conventions, idioms, no second parallel way.

When to use

Checks that a change follows the project's own conventions and the language/framework's idioms: formatter applied, idiomatic constructs over clumsy equivalents, recurring problems solved the same way the codebase already does, no second parallel way to do the same thing, consistent naming/casing/imports/file layout. Use when reviewing style, conventions, idioms, framework usage, or consistency with the rest of the codebase.

Shape: diff. Written for concrete code; not meant for design docs or plans.

Reviewer discipline

Report only real problems. If the code correctly handles the case, reply "No findings" and stop — do not invent issues. This guards against false positives on correct code; still report every genuine issue you do find, with its full detail.

Defects are the default; improvements are opt-in. By default this lens is defect-only: do not suggest changes to code that is already correct. When the team has opted up into improvement suggestions, a finding on already-correct code is admissible only as nit-severity, route: implementer (the author applies, defers, or ignores), and must clear the non-configurable anti-churn floor: it must genuinely improve — never offer a merely equivalent alternative — and must converge (once a dimension is as good as you can confidently make it, stop; never oscillate A→B then B→A, never re-order to an equivalent state). Defects keep the strict bar above regardless of this setting.

Team preferences. If the reviewed repo has .code-quality-atlas/preferences.md, apply it before reporting: a repo's .code-quality-atlas/preferences.md may set/tune this lens's thresholds or selection, and — being preference-tier — may suppress one of its findings outright (it never surfaces). Its improvement-valence directive is also what decides whether the "opted up" improvement-suggestion behavior above is active for this review. Absent the file, apply this lens's defaults exactly as written above.

Pre-existing defects in touched code are surfaceable, not yours to fix. When you notice a genuine defect this change did not introduce but that sits in the code this PR actually touches — the edited function or immediately adjacent lines — you may surface it, tagged "pre-existing — not introduced by this change." Like improvements it is opt-in and default-quiet (off unless the team opts up), route: implementer, and non-blocking: it informs the author's fix-now / file-a-ticket / ignore call and never sets this PR's verdict, because the diff did not cause it. Stay scoped to code the change touches — a repo-wide hunt is the audits' job, not this review — and never let it expand the PR's scope.

Top checks

The head of the full checklist — enough for a first pass without opening any reference file:

• Does the change follow the project's own conventions? Read .eslintrc/.rubocop.yml/ruff.toml/.editorconfig/style guide first; the codebase's established choice wins over personal preference.
• Is the code formatted by the project's formatter? (Unformatted code where Prettier/Black/gofmt exists is an automatic finding.)
• Does it use the idiomatic construct for this language/framework, or a clumsy non-native equivalent? (comprehension vs. manual loop; Result/error-as-value vs. exceptions where one was chosen; framework router/ORM idiom vs. hand-rolled.)
• Pattern consistency: does this solve a recurring problem the same way the codebase already does (error shape, DTO/serialization, DI style, test layout)? Divergence needs a stated reason.
• Are naming/casing conventions uniform across the symbol kind? No mixed snake_case/camelCase for one role (cross-links #5).
• Import ordering / module structure / file layout consistent with siblings? (New file where a reader expects it.)
• Are strings/messages/log formats consistent with existing ones (cross-links #16)?
• Does it avoid introducing a second way to do the same thing (a parallel util, competing abstraction) when one exists (cross-links #11/#9)?

Mechanizing these checks

Where a finding here is one a tool can catch deterministically, surface that as an advisory route: implementer note next to the finding: the hand review caught it this time, and wiring the matching tool from reference/tool-rules.md into CI gates it going forward. This is a suggestion to mechanize, not a defect — it never blocks a verdict, and it falls away on a repo that already runs the tool.

Process notes. If this lens misfired on this change — flagged correct code, missed an obvious issue squarely in its own scope, or its checklist didn't fit the change shape — say so in one line under synthesizing-review-findings's Process notes appendix; that is not a defect finding. Say nothing if the lens worked as intended — never invent a process note to fill the section.

Going deeper

• reference/heuristics.md — the full checklist; open it when the change sits squarely in this lens's domain.
• examples.md — concrete good/bad findings, and the output format to match.
• reference/tool-rules.md — static-analysis rules covering the mechanical subset; for wiring up linters, not needed for the judgment review itself.
• reference/sources.md — the research behind each check; for provenance, not needed during a review.