msd-core/docs/how-to/scope-code-review-depth-by-path.md

How to scope code review depth by path

Goal: Escalate /msd-code-review to deep for sensitive directories (auth, billing, payments) while the rest of the repository keeps reviewing at the project's normal default — without having to remember --depth=deep on every review that happens to touch one of those paths.

Prerequisites: A project with /msd-code-review enabled (workflow.code_review: true). This guide assumes you already have a working default depth via workflow.code_review_depth; see Configuration Reference if you don't.

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The shortest working sequence

1. Set the global default, if you haven't already:

   msd config-set workflow.code_review_depth standard
   

2. Add path-scoped rules to workflow.code_review_depth_overrides in .planning/config.json. It's an ordered array of { "paths": [...], "depth": "quick" | "standard" | "deep" } objects:

   {
     "workflow": {
       "code_review_depth": "standard",
       "code_review_depth_overrides": [
         { "paths": ["src/auth"], "depth": "deep" },
         { "paths": ["src/billing"], "depth": "deep" }
       ]
     }
   }
   

3. Run the review as usual:

   /msd-code-review 12
   

4. Read the provenance line in the output to confirm which rule (if any) fired — see Read the resolved-depth line below.

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Worked example: escalate src/auth and src/billing, leave everything else at standard

With the config above, a phase that only touches src/lib/formatter.ts reviews at standard (no rule matches, falls through to the global default). A phase that touches src/auth/token.ts and nothing else in an escalated path reviews at deep, because a rule matched.

Escalation is whole-review, not per-file. If a phase touches both src/lib/formatter.ts and src/auth/token.ts, the entire review — including formatter.ts — runs at deep. Depth is a single scalar handed to the reviewer agent; one matched sensitive file is enough to raise the whole review, so a sensitive file is never reviewed shallowly because it shared a phase with unrelated code.

Matching is by whole path segment, not substring:

Changed file	Matches rule src/auth?
src/auth/token.ts	Yes
src/auth (the file itself)	Yes
src/authfoo/x.ts	No — authfoo is a different segment
docs/src/auth/x.ts	No — prefix is anchored at the path root, not a substring search

Matching is case-sensitive, following git: a rule written Src/Auth will not match src/auth/x.ts.

Rules win over the global default, even when weaker. If workflow.code_review_depth is deep but a matched rule says quick, the review runs at quick — the rule always replaces the global for files it matches. This is deliberate: if the strongest tier always won, a quick or standard rule could never actually take effect whenever the project default was deep, making it silently inert.

Only globs are rejected — not the paths themselves. workflow.code_review_depth_overrides supports directory-prefix strings only (src/auth, not src/auth/**). There is no glob engine in this project; write the prefix and let segment-aware matching do the rest.

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Read the resolved-depth line

Every review prints one line naming the resolved depth and why:

Review depth: deep (matched rule 0: src/auth)

The parenthetical names the source:

Provenance text	Meaning
from --depth flag	The --depth= CLI flag was passed; it always wins over both rules and config.
matched rule N: <path>	Rule at index N (0-based, in declaration order) matched on prefix <path> and set the depth.
from workflow.code_review_depth	No rule matched this review's file set; the global config value was used.
default	Neither a rule, config value, nor flag applied; the built-in standard default was used.

If the review scope exceeds 50 files and the resolved depth is deep, the existing large-scope downgrade still fires — but now it names the rule it overrode:

Switching from deep to standard depth for large file count (overrides matched rule 0: src/auth).

A configured sensitive-path policy is not exempt from this downgrade — the same guard that downgrades --depth=deep on a large scope also downgrades a rule-sourced deep.

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Nothing to report vs. could not look

Two outcomes look similar but mean opposite things:

• A rule matches nothing. This is not an error and is not reported specially — it means this review simply didn't touch any path the rule covers. The provenance line falls through to from workflow.code_review_depth or default, exactly as if the rule didn't exist. This is "nothing to report": the policy exists, was checked, and had nothing to say about this particular review.
• The configuration is rejected. This is "could not look": the review halts before doing any file-level work and prints every collected validation error. Never conflate the two — a validly-configured rule set with no match for this review is a healthy, silent no-op; a malformed rule set is a hard stop.

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Configuration error reasons

If workflow.code_review_depth_overrides is malformed, /msd-code-review prints one error per defect (all of them, not just the first) and stops — it never silently falls back to a default depth. Errors report the reason as one of the following typed values (from src/code-review-depth.cts):

Reason	Meaning	Fix
not_an_array	workflow.code_review_depth_overrides itself is not an array (object, string, number, null, etc.)	Set it to an array of rule objects, or [] to disable overrides.
rule_not_object	An entry in the array is not a plain object (a string, an array, null, 0, etc.)	Each entry must be a { "paths": [...], "depth": "..." } object.
paths_malformed	A rule's paths is missing, not an array, empty, or contains a non-string entry	Give paths a non-empty array of strings, e.g. ["src/auth"].
invalid_depth	A rule's depth is missing or not one of quick, standard, deep	Set depth to exactly one of quick, standard, or deep.
glob_unsupported	A rule path contains * or ? (e.g. src/auth/**)	Use a directory prefix instead: src/auth, not src/auth/** or src/auth/*.ts.
path_traversal	A rule path contains a .. segment	Remove the .. segment; write a plain repo-relative prefix.
path_absolute	A rule path is absolute (/src/auth, C:\src\auth)	Use a path relative to the repo root: src/auth, not /src/auth.
path_empty	A rule path is empty, whitespace-only, or normalizes to empty or .	Give the path real content, e.g. src/auth rather than "" or ".".

Each printed error names the rule index (and, where applicable, the offending path or depth value) so you can find the exact entry to fix without guessing which rule in the array is broken.

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Related

• Configuration Reference — full schema for workflow.code_review_depth_overrides and workflow.code_review_depth
• Feature Reference — Code Review Pipeline — why escalation is whole-review and why v1 is prefix-only, not glob
• /msd-code-review — command reference and the --depth= flag
• docs index