# What is not compared

> Headers, query parameters, enum values and formats, which no change in makes can-i-deploy fail.

The grammar has no place for the items below, so a change in any of them never makes `can-i-deploy` fail.

- **Headers.** A provider that starts requiring one, and a consumer that stops sending one, both pass.
- **Query parameters.** A renamed parameter, a newly required one, or a change in how pagination is requested is not a break.
- **Enum values.** A `string` is a `string`: a provider that starts returning a fourth value of `status` is compatible with a consumer that handles three.
- **Formats.** A `date-time` string, an email and free text are the same `string`.