FAQ

How is this different from AGENTS.md?

AGENTS.md tells a coding agent how to work in a repo. DOPPELGÄNGER.md tells any model how you write. Keep both. Point AGENTS.md at the voice file when the agent writes user-facing copy.

How is this different from BRAND.md?

BRAND.md and Brand Context Protocol cover strategy, voice, and visual identity. DOPPELGÄNGER.md is voice only. No logo rules, no palette, no layout.

Why is there no hosted loader?

A hosted loader becomes an account, an API, and a lock-in. The convention is the file. Paste it, attach it, or @ it.

Can the file hold secrets?

No. The spec forbids keys, passwords, tokens, and unpublished personal data. It also forbids invented facts, metrics, and clients.

How do I make the file accurate?

• Prefer real writing you already sent or published — email, posts, site, blogs — not AI drafts.
• Scrub secrets and private third-party details before pasting samples.
• Keep 3–7 short samples across registers (email, social, web, etc.). Quality beats volume.
• When replies stop sounding like you, refresh samples and bump Meta version and updated.
• Re-run on a schedule only if that helps you; the file does not expire.

Person or company?

Meta kind is person or organization. The sections are the same. An organization file speaks as the company.

Which language?

Spec 0.1 is English only. Meta language is a BCP 47 tag. Use en.

What is the license?

The spec, the example, and this site are public domain under CC0 1.0. Your own file can use another license. Name it in Meta.

Where is the canonical site?

https://doppelganger.md. Until DNS points there, run node scripts/site.mjs preview.