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contentVercel

Consistent Placeholders in Samples

MUST

MUST: Use one loud, obviously-fake placeholder convention across all code samples — `YOUR_API_TOKEN_HERE` for strings, `0123456789` for numbers — never a mix of `<your-token>` / `xxx` / `abc123` / `[INSERT KEY]`. (This is about fill-me-in tokens in docs, not the HTML `placeholder` attribute.)

Use one placeholder convention across every code sample: YOUR_API_TOKEN_HERE for strings, 0123456789 for numbers

Bad

Good

Why it matters

This is about the fill-me-in tokens inside documentation and code samples, not the HTML placeholder attribute on an input — that one is covered by the separate rule against using a placeholder as a label or a value. When a snippet mixes <your-token>, xxx, abc123, and [INSERT KEY], the reader cannot tell which strings are literal and which are theirs, so they paste a sample verbatim and get a 401.

A single loud, obviously-fake convention — screaming snake case for strings, a monotone digit run for numbers — is unmistakably a slot, greppable, and safe to search-and-replace across a whole page.

Built by Gleb Stroganov, design engineer at Evil Martians.

The rules come from other people's skills and guidelines — Vercel, Rauno Freiberg, @Ibelick, impeccable, Emil Kowalski, Tailwind, RAMS — each one credited on the Sources page. The work here is extraction and wiring: every rule is pulled into one corpus, given a good and a bad example you can operate, a MUST/SHOULD/NEVER rule an agent can paste, and a link back to where it came from.