How to Structure Error Messages in Go (lowercase, no punctuation)

Error Handling

2026-04-17T12:05:42+00:00

Use lowercase error messages without terminal punctuation to align with Go standard library conventions.

Structure Go error messages in lowercase without terminal punctuation to match the standard library convention. Use errors.New with a plain string or fmt.Errorf with a format string, ensuring the message starts with the package name if it aids identification.

import "errors"

var ErrNotFound = errors.New("archive/tar: file not found")

func writeHeader(hdr *Header) error {
    if hdr.Size < 0 {
        return fmt.Errorf("archive/tar: negative file size %d", hdr.Size)
    }
    return nil
}