All modules containing functions should have corresponding .mli files with comprehensive documentation. The .mli file must include: 1. **Module purpose**: A clear, high-level description of what the module does and why it exists 2. **Function documentation**: Comments explaining what each function does, its parameters, return values, and any special behaviors 3. **Type documentation**: Clear explanations of custom types and their fields 4. **API behavior notes**: Documentation of important behaviors like error handling, redirects, or resource management Example structure: ```ocaml (** High-level module purpose and goals. This module handles X by doing Y, and is primarily used for Z. See also {!Related_module} for similar functionality. *) (** Custom type representing... *) type analysis_flags = { secrets_validators : bool; (** Enable secrets validation *) historical_scan : bool; (** Scan historical data *) (* ... *) } (** Execute a command request. @param request The command to execute @param context Current execution context @return Result of execution or error Note: Automatically handles 307 redirects for binary downloads. *) val handle_execute_request : request -> context -> (result, error) Result.t ``` This ensures that module interfaces are self-documenting and that ocamldoc can generate useful documentation. Avoid vague function names without proper documentation, and always explain the module's role in the larger system.