Draft prompt highlighting

bb 0.43.3·SDK 0.4.104·pinned e865697 (desktop-v0.43.3)

stable The composer #3 in group Show on the zone map

Styles text ranges as the person types a prompt, without changing the text. With this, a plugin can:

What it gives you

• Match ranges in the draft prompt, such as a ticket number or the word TODO
• Change only how those ranges look; the text the agent receives is untouched
• Re-run its matcher on every keystroke
• Observe the draft prompt and its @-mentions as they change, read-only
• Remove a plugin-owned mention from the draft, including its visible text
• Respond after a local message is successfully sent or queued; failed sends do not notify

API

Each symbol links to the pinned commit it was read at.

• ComposerRichTextSpec interface
• ComposerStructuredDraft interface
• PluginComposerApi.experimental_removeMention method
• PluginComposerApi.experimental_onSubmitted method

Brief for agent…as a bb mentionAdd to set

The brief is Markdown, written for a coding agent: what the capability is, where it registers, every SDK symbol with a pinned permalink, the rules that bite, and what done means.