About Reference tools
Some knowledge is needed often but rarely memorised in full — exactly what 422 means, the correct Content-Type for a font file, or whether a script should be 755. These reference tools make those answers instant and unambiguous, with enough context to act on them confidently. They are fast, searchable where it helps, and run in your browser. Think of this category as the quick-reference shelf you keep within arm’s reach while building and debugging.