Send fidelity

Send fidelity means the Slack render of a broadcast always matches the preview — Stet uses the same render code for both, so what you see is what lands.

One render path

The composer's preview pane and the send pipeline call the same render functions over the same block data. There's no separate preview renderer to drift out of sync — a preview and a send are two calls into one code path, not a preview that merely resembles the send.

Verifying before you send

Because preview and send share that one path, a block's formatting, line breaks, and per-block audience visibility in the preview are exactly what posts to the channel — not an approximation.

Send test… confirms it once more: it posts the real render to you as a Slack DM before an audience ever sees it.

Guardrails against broken sends

A few checks exist because the guarantee only holds if a broadcast can't send something the preview can't faithfully represent:

• A button without a link blocks the send with a 422 instead of shipping a button that does nothing when clicked.
• A block set that renders to zero Slack blocks for a channel fails that channel immediately, instead of posting a blank message.
• Composing from Markdown through the REST API rejects unsupported constructs — tables, raw HTML, nested lists — with a 400, rather than mangling them into something that wasn't written.

The name

Stet is the proofreader's mark for "let it stand" — an instruction to leave marked text exactly as is. That's the guarantee this page describes: what you mark up in the preview is what stands in the channel.