Make a one-page decision memo that doesn't oversell an option
Two options, one page, a decision on Thursday. The bold headline is what people will remember, so it had better say only what the sources say.
What you'll make
a one-page decision memo with a plain headline, each option’s known facts and gaps, a source ID beside every claim, and the open questions in view.
What you'll need
checked facts for each option, the decision the reader has to make, ChatGPT, Claude, Copilot or Gemini in your work account, and about 20 minutes.
Example result.
| Option A: renew current tool | Option B: calendar booking | |
|---|---|---|
| Cost | £1,800 a year, quote supplied (S1) | Not estimated yet (S2) |
| Status | Contract ends 31 January (S4) | Proposed by IT; scope pending (S2) |
| Open | — | Ready before 31 January? Desk booking? |
1. Label the facts and name the decision
Give each fact a short ID (S1, S2…). Then write the decision in one line: what the reader has to choose, and by when if the source says. List what you don’t know yet. Don’t ask for a persuasive case before you know which claims the sources support.
Create a one-page decision memo answering [decision] from these
checked facts only. Use a plain headline, one short section per option
and a list of open questions. Put the source ID after every claim.
Keep proposed, agreed and finished as different states. Leave missing
costs or dates as "not known" rather than estimating them. Use layout
to help scanning, not to make one option look stronger than the
sources show.[decision] is the one-line decision, such as “renew the room-booking tool or switch to calendar booking”.
Why this works: the memo’s structure comes from the facts and the gaps, so a missing quote shows up as a gap rather than a guess.
What you should see: a draft memo where every claim ends in a source ID and the open questions have their own section.
2. Ask for the evidence map before polishing
Before anyone formats it, check the claims.
List every claim in the memo, including the headline and any labels,
with its source ID and the exact passage behind it. Mark each as fact,
proposal or open question. Flag any wording, colour or icon that
suggests a result, cost or approval the sources don't contain.Why this works: headlines and labels are where overselling hides. Listing them as claims makes them checkable.
What you should see: a short table of claims. Anything without a passage is a candidate for deletion or the open-questions list.
3. Put it in the format the reader will use
| Tool | Where to build the page |
|---|---|
| Claude | Ask for it as an artifact; it opens beside the chat and can be exported. Needs Settings › Capabilities › Code execution and file creation |
| ChatGPT | Ask it to “use canvas” to edit the memo beside the chat, then download it |
| Copilot | In Word, open Copilot, describe the memo and type / to pick the source file, then Generate |
| Gemini | Ask for the memo in the chat and paste it into a Google Doc |
Open the result as the reader will see it: printed, on a phone or in the email. Check the source IDs survived the formatting.
Why this works: a memo the reader can’t open, or that loses its source IDs on export, isn’t a one-page memo any more.
What you should see: one page, readable at its real size, with the source IDs still in place.
Check the result
- The headline says nothing that isn’t in a source.
- Every option shows its gaps as clearly as its facts.
- A missing cost is “not known”, not an estimate or a blank.
- Proposed options read as proposed, not as ready.
The usual failure: the headline picks a winner the sources don’t support. A missing quote reads as “cheaper”, a proposal reads as “ready”, and the layout gives it the biggest box. Spot it by putting your finger on the headline and finding its source ID.
The headline says [claim], but the sources say only [what they say].
Rewrite the headline and any related label so they match the sources.
Keep the one-page structure and the open questions. Do not add a new
figure or approval to make the options look comparable.[claim] is the oversold headline; [what they say] is the source wording, with IDs.
Worked example: renew or switch the room-booking tool
Fictional example. Owen, an office manager, has to recommend whether to renew the room-booking tool. His facts:
S1 Option A: renew current tool. Quote supplied: £1,800 a year, 12-month term.
S2 Option B: book rooms through the company calendar. Proposed by IT; cost and scope not yet estimated.
S3 Staff survey (31 responses): 19 said the current tool is slow on mobile.
S4 Current contract ends 31 January.The first memo’s headline: “Switch to calendar booking: cheaper and ready to roll out.”
- The failure. S2 gives no cost, so “cheaper” has no source. “Ready to roll out” turns a proposal into a plan. The layout put B in a large green box.
- The repair. The repair prompt, with that headline and S2’s wording, gave: “Renew at £1,800 a year (S1), or switch to calendar booking (S2: proposed, cost not yet estimated). Contract ends 31 January (S4).” The example result above is the repaired body.
- What Owen asked for next. A cost estimate and a date from IT, and whether calendar booking covers desks. The memo made those questions obvious; the first draft hid them.
Task kit for this job: Download (ZIP) · Reusable instructions
Go deeper
Keep a short text version with the visual
A reader should understand the decision and its limits without relying on colour or layout. Put the same facts and source IDs in a plain paragraph at the bottom, or in the email that carries the memo. Don’t let the text version strengthen the conclusion.
Compare costs only on the same basis
If cost decides it, check both options use the same units, term and included fees before they sit side by side. The supplier-unit comparison shows how a neat price table can still compare different things.
Link the memo to the source version
Note the date or version of the sources the memo used. When a source changes, such as IT’s estimate arriving, review the affected lines instead of assuming the old memo still holds. For a longer summary with a passage-level trail, see executive summaries with a source trail.