Support custom directory names via --allow-dir flag

[mpolce-squareup]

Problem

Skills with domain-specific directory layouts (e.g. domains/, databases/) are incorrectly flagged by the token ratio check as "not structured as a skill" because only references/, scripts/, and assets/ are recognized as standard directories.

The countOtherFiles function in structure/tokens.go counts all files in unrecognized directories as "non-standard" tokens. When these exceed 25,000 tokens and are 10× the standard content, the checkSkillRatio check in validate.go emits a blocking error:

Error: this content doesn't appear to be structured as a skill — there are 92,973 tokens of non-standard content but only 5,432 tokens in the standard skill structure

This blocks skills that intentionally organize content into custom directories (e.g. a risk analysis skill with a domains/ directory containing per-domain reference files).

Proposed fix

Add an --allow-dir CLI flag (repeatable) that treats named directories as standard:

• Excludes them from the non-standard ("other") token count in countOtherFiles
• Suppresses the "unknown directory" structural warning in CheckStructure

Implementation

A working implementation with tests is available at: https://github.com/mpolce-squareup/skill-validator/tree/mpolce/allow-custom-dirs

Changes:

• structure/validate.go: Add AllowDirs []string to Options
• structure/tokens.go: countOtherFiles skips directories in AllowDirs
• structure/checks.go: CheckStructure skips warning for directories in AllowDirs
• cmd/check.go: Add --allow-dir StringSliceVar flag

All existing tests pass + 7 new tests added.

[mpolce-squareup]

Hi @dacharyc , we had several teams' pull requests get blocked with this check in the CI with skill-validator. I implemented a workaround with our forked instance of skill-validator so as to unblock the PRs, but I was wondering if we need a new CLI flag for named directories?

[dacharyc]

Hey @mpolce-squareup - I implemented the --allow-dirs flag in v1.4.0 - it landed in #41

Can you say more about how your implementation differs and why it's needed?

[mpolce-squareup]

After checking our CI workflow for invoking skill-validator again, I verified that the workflow check was the issue, not skill-validator. The workflow never passed --allow-dirs, so domains/ was still counted as 89k tokens of non-standard content, triggering the ratio error. So the issue wasn't actually with the release, so I'm currently correcting our CI workflow check process for this. But thank you for implemented the flag in v1.4.0. I'll close this ticket as a non-issue.