Case Converter — camelCase, snake_case, kebab-case and Back
Different ecosystems settled on different conventions for multi-word identifiers, and any system that talks to another crosses at least one boundary between them. This converts a name from one convention to another, in bulk, without the transcription errors that come from doing forty of them by hand.
When it helps
Boundaries are where the work is. A JSON API using camelCase feeding a database using snake_case, a set of CSS custom properties derived from a design token file, environment variables generated from a configuration schema. Converting a long list by hand is slow and, more to the point, unreliable — the one you mistype fails at runtime in a way that is hard to spot in review because it looks almost right.
Worth running automatically
The conversion itself belongs in code at the boundary rather than in a tool, and the tool is for the one-off migration. What is worth automating is detecting when a mapping breaks: a field renamed on one side of an API arrives as null on the other, which is not an error anywhere. Validating the actual response body of an endpoint against expected field names catches a silent rename that a status-code check cannot see.
What you get out of it
Fast, accurate bulk renaming at the seams between systems that disagree about naming, without the transcription mistakes that make a runtime failure look like a typo review missed.