The two-sentence ceiling, and why it holds
It is tempting to give the host a fuller paragraph, particularly when the host is you and the session is the one you have been trying to organise for a quarter. Resist it for a practical reason: a visitor deciding whether to register reads for competence and for shape. Anything past two sentences next to the speaker's name stops being information and starts being noise, and the coverage line beneath it is what the reader is actually hunting for.
Keep the same two sentences in the spoken introduction, so the written block and the handover agree, and revisit the line if the arrangement changes. If you take on a co-host for the next date, the page edits while the address holds โ both names appear, each with their function, and nobody needs a new link to see the change.