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Herald Docs

Demo Mode

Demo mode starts Herald with synthetic data. It is useful for trying the interface, recording demos, and testing visual changes without touching a real inbox.

Terminal window
make build
./bin/herald --demo

Demo mode skips real IMAP setup, uses a fake account, and does not require SMTP credentials. Demo AI features are deterministic and run offline, so classification, semantic search, chat, and quick replies can be exercised without Ollama.

Browser demo

Section titled “Browser demo”

You can combine demo mode with ttyd:

Terminal window
ttyd -W ./bin/herald --demo

Regenerate demo GIFs

Section titled “Regenerate demo GIFs”

Demo tapes live in demos/*.tape, and generated GIFs go to assets/demo/*.gif.

Terminal window
brew install vhs
make build
make build-mcp
for f in demos/*.tape; do vhs "$f"; done

Run tapes from the repository root because they reference ./bin/herald.

See Demo GIF Workflow for the full recording flow.

What demo mode is not

Section titled “What demo mode is not”

Demo mode is not a local mailbox emulator. It is a presentation and UI testing mode with synthetic data. Use a real IMAP account or a test IMAP server when you need to verify provider behavior.