file-search-on: Skill for Claude Code

Add Content Type

A "content type" is anything Detect() can identify and Walk can tag. Registering one is mostly mechanical: drop a file in internal/content/, implement four methods, register it, done. The wrinkle is the Attributes(ctx, fsys, path) method — if it returns any type-specific keys, you also need the extend-cel-schema workflow to make those keys CEL-visible.

What gets registered

A type is identified by its Name() (e.g. "json", "image/png") and detected by either:

• Extension match — .json, .md, etc. Tried first.
• Magic-byte prefix — first 512 bytes of the file. Used as a fallback when the extension doesn't match.

Either or both can be empty (extension-only or magic-only types are valid). Registration is a side-effect of init() calling content.Register(...) — there is no central list to edit.

Quick start (non-image, no attributes)

For a type like CSV that you want detected but where you don't (yet) care about per-file attributes:

1. Copy the template:

   cp .claude/skills/add-content-type/templates/content_type.go.tmpl internal/content/csv.go
   

2. Fill in csv.go: replace <typename>, <TypeName>, <name>, <.ext>, magic bytes (or nil).
3. Implement Attributes — for now, just return Attributes{}, nil.
4. Run go build ./... and go test ./... — no test edits required for a no-attribute type.
5. Run go run ./cmd/file-search-on --list — your new type appears under "Registered content types".

Quick start (with attributes)

If Attributes(ctx, fsys, path) returns type-specific keys (e.g. csv_columns, csv_rows):

1. Steps 1–3 as above, but make Attributes return the keys.
2. Then run the extend-cel-schema skill for each new key — declare the CEL variable, add to the activation defaults, add a switch case, and document in Schema().
3. Run python .claude/skills/extend-cel-schema/scripts/audit_attributes.py — must pass.
4. Run go test ./....
5. Add a unit test in internal/content/csv_test.go exercising the new type.