“Just checking in about the thing we discussed” makes perfect sense to the person typing it. On the receiving end, it can mean searching old messages to work out which thing, what changed, and whether an answer is needed at all.
Put the request near the top
Try “Can you choose between these two times by Thursday?” Then add the background. The reader can immediately see the job. If there is no action required, say so: “For your information; no reply needed.” Those few words can save someone an unnecessary task.
Supply the missing piece
Include the relevant link, the two options, or the short excerpt that matters. Avoid making someone hunt for a document you already have open. If you are changing an arrangement, state the new plan in full rather than expecting them to combine this message with three earlier ones.
Be clear about dates. “Next Friday” can become confusing when a message is read later. The actual date helps everyone land on the same day.
Keep warmth, lose the fog
A friendly sentence is welcome. So is a thank-you. You do not need to strip every message down to commands. Just look for wording that hides the point: “at some stage,” “when convenient,” or “thoughts?” might be too vague if you need a specific answer.
Read the message once as the recipient. Could you respond without asking what it means? If yes, send it. If not, fix the missing detail. Clarity is a practical form of consideration, especially when everyone is reading on a small screen between other things.