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How to Turn a Decision Log Entry into a Prompt for a Review Model

Antonio Evans7 min read

A desk seen from above: an open notebook with a handwritten decision entry on the left page and a printed prompt with labeled sections (Decision, Options, Evidence, Assumptions, What to check) on the right.
Key points

Key points

  1. 1A decision log entry becomes a review prompt only when it is restructured into four labeled blocks: decision, options considered, evidence, and assumptions.
  2. 2Every evidence line must point to a source (deck slide number, metric cell, or document paragraph) instead of paraphrasing the claim.
  3. 3An instruction header that names the review task, the allowed verdicts, and a quote-don't-rewrite rule is what stops the model from composing new reasoning.
  4. 4A fixed output table (claim, source found, verdict, quoted line) makes each check auditable and turns invented rationale into a visible failure.

Why a log entry is not yet a prompt

A decision log entry is written for humans who were in the room. It says "growth is strong" or "customers asked for tiered pricing" because everyone reading it already knows which chart and which interview that refers to. The entry is a memory aid, not an evidence package.

A review model reads nothing you did not paste. If the entry says "strong pipeline," the model has no way to know whether pipeline lives on slide 11 of the deck, in a CRM export, or nowhere at all. Pressed to be useful, it will produce a fluent paragraph about pipeline strength that sounds like analysis and is actually pattern completion. That is the invented rationale problem, and it starts with the input, not the model.

The fix is a format conversion, not a better prompt trick. You take the entry that exists in your tracker and rewrite it as a checking task with explicit source pointers, then hand the model both the rewritten entry and the files it should look inside. The structure below borrows the fields that standard decision logs already capture: the choice, the alternatives weighed, the reasoning, the owner, and the date, as described in the monday.com guide to decision logs and Plane's decision log breakdown.

The four-block conversion

Rewrite the entry into exactly four blocks. Keep each one short. The labels do the work; prose between them does not.

BlockWhat goes in itWhat must not go in it
DECISIONOne sentence: what was chosen, by whom, on what dateJustification, adjectives, outcomes
OPTIONSEach alternative that was seriously considered, one line each, including "do nothing"Straw options nobody debated
EVIDENCEOne claim per line, each ending in a pointer such as (deck s7) or (metrics!C4, 2024-03-31)Unsourced numbers, "data shows," "customers say"
ASSUMPTIONSBeliefs the decision depends on that the evidence does not proveAnything already covered by an evidence pointer

The evidence block is where most of the value sits, and where most entries fail on the first attempt. Compare a typical log line with a converted one:

  • Log: "Enterprise demand is picking up, so we should add a team tier."
  • Converted: "Three of the last five signed contracts asked for SSO before signature (deck s9; calls sheet rows 14, 19, 22)."

The second version is longer, but every clause can be checked against something the model can open. The first version forces the model to guess, and guessing is where fabricated support enters the review. The discipline mirrors what investors expect in a deck: J.P. Morgan's startup banking guidance stresses data-backed problem statements and traction evidence over assertion, and a reviewer model can only apply that standard if the evidence is addressable (J.P. Morgan on pitch decks).

A practical rule: if you cannot name the slide, the cell, or the paragraph behind a line, move it to ASSUMPTIONS. That keeps the claim alive in the review but marks it as unproven, which is exactly the verdict you want the model to return.

Replacing vague claims with source pointers

Source pointers need a grammar, or the model will invent addresses. Pick one convention and state it in the instruction header. Three formats cover most decks and models:

  1. Deck: (deck sN) where N is the slide number, counted from the title slide as 1.
  2. Spreadsheet: (metrics!<cell>, <as-of date>), for example (metrics!C4, 2024-03-31).
  3. Document: (memo pN, para M) for written memos and research notes.

The as-of date matters because reviewers check freshness as much as presence. A margin claim sourced to a cell from two quarters back is found but stale, and you want the model to say so rather than pass it. Financial projection slides fail precisely because the numbers on them are not anchored to current pipeline; Waveup's review of hundreds of decks argues year-one figures must be backed by signed pipeline rather than modeled growth, which is a claim a model can verify only if you point it at the pipeline source (Waveup on financial projections).

Send the source files with the entry in one message. Extract the deck to text with slide markers, export the metrics sheet as CSV, and paste both beneath the entry inside clear delimiters. The Patterns review of prompt engineering techniques notes that delimiters separating instructions from content are a basic and reliable way to keep a model from confusing the two (Chen et al., Patterns).

The instruction header

The header is five to eight lines and never varies between entries. It does four jobs: names the task as a check, lists the allowed verdicts, forbids rewriting, and fixes the output shape.

TASK: Check the DECISION ENTRY below against the attached sources.
You are not writing or improving the entry.

VERDICTS (use only these):
  SUPPORTED      the source says what the claim says
  PARTIAL        the source says something weaker or narrower
  NOT FOUND      no source in the attachment contains it
  CONTRADICTED   a source says the opposite

RULES:
1. Quote the exact line from the source. Never paraphrase a quote.
2. If the pointer is wrong but the claim is findable elsewhere, quote
   the real location.
3. Do not propose new reasoning, new numbers or new recommendations.
4. If you cannot quote it, the verdict is NOT FOUND.

OUTPUT: one markdown table, columns: Claim | Source found | Verdict | Quoted line.
Then one final row per ASSUMPTION, verdict UNPROVEN unless a source proves it.

The verdict on assumptions is the subtle part. A model asked to "check assumptions" will happily argue for or against them, which reintroduces composition. Forcing UNPROVEN keeps the model in check mode and leaves judgment with you. That split, deterministic checking by the model and judgment by the human, is the distinction the broader prompt engineering literature draws between instruction design and evaluation design (Maxim's practitioner guide).

If your team runs several review passes, keep the header in version control and change it deliberately, treating edits as a hypothesis to test against a fixed set of entries, as the local-first prompting guide recommends for repeatable review work (LocalChat best practices).

A worked pricing example

Here is a raw entry as it might appear in a founder tracker, written in the usual shorthand:

Raised prices on the Team plan from $20 to $29 per seat. Growth is strong and competitors are more expensive, so churn should hold. We can push the annual discount later if needed.

Converted into four blocks:

DECISION
On 2024-04-02 the pricing committee raised Team from $20 to $29 per
seat, effective 2024-05-01. Owner: Head of Revenue.

OPTIONS
A. Keep $20 and add a usage fee.
B. Raise to $29 flat, keep annual discount at 20%.
C. Raise to $35 and drop the annual discount.
D. Do nothing until the next quarter.

EVIDENCE
E1. Team-plan churn averaged 1.9% monthly in the six months to
    2024-03-31 (metrics!B7, 2024-03-31).
E2. Two competitors list entry seats above $25 (deck s14).
E3. 11 of 14 renewal calls raised price before value (calls sheet
    rows 3 to 16).
E4. Gross margin on Team was 71% in Q1 (metrics!D2, 2024-03-31).

ASSUMPTIONS
A1. Churn stays under 2.5% monthly for two quarters after the raise.
A2. The annual discount remains a strong enough incentive at $29.
A3. Sales cycle length does not change materially.

Now the model's job is narrow. For E2 it opens deck slide 14 and quotes the competitor lines, or returns NOT FOUND. For E1 it finds cell B7, quotes the churn figure, and notes whether the pointer is right. For E4 it may find that D2 holds a different quarter or a blended margin, giving PARTIAL or CONTRADICTED. The three assumptions return UNPROVEN, which is the honest answer and the one that tells you what to watch after the change.

A typical output looks like this:

ClaimSource foundVerdictQuoted line
E1 churn 1.9% monthlymetrics!B7SUPPORTED"Team churn, monthly, 6-mo avg: 1.9%"
E2 two competitors above $25deck s14PARTIAL"Competitor X entry seat: $24 list, $29 after onboarding"
E3 price raised in 11 of 14 callscalls sheetNOT FOUND(no matching column in attachment)
E4 Team gross margin 71%metrics!D2CONTRADICTED"Blended gross margin Q1: 71%; Team only: 64%"
A1 churn under 2.5%noneUNPROVEN(assumption)

Read the verdicts as a punch list: one claim needs a better source (E3), one is weaker than stated (E2), one is wrong (E4), and one slipped past everyone (E1). That is a fifteen-minute pass that would otherwise cost a meeting. The same check applies to investor-facing versions, where deck claims about market size and traction are the ones reviewers press on, as the deck examples collected by Slidebean and Figma show in their traction and market slides.

Failure modes to watch for

Even with the header in place, five failures recur. Each has a specific countermeasure.

FailureWhat it looks likeCountermeasure
Invented rationaleModel adds "this is consistent with industry norms" with no quoteRule 3 plus the rule that no verdict appears without a quote
Pointer driftModel cites slide 14 when the number is on slide 16Ask it to report the real location when the pointer is wrong
Silent compactionModel merges two claims into one rowOne claim per row; count rows against evidence lines
Assumption advocacyModel argues for or against an assumptionFixed UNPROVEN verdict for the assumptions block
Helpful rewritingModel returns an improved version of the entryState that the entry is not to be edited; reject any output without the table

The assumption-advocacy failure is the most tempting to allow, because a model that argues is more interesting to read. Resist it. The moment the model builds an argument, you are reading a composition and cannot tell which parts came from your files. The investor-deck literature is full of warnings about projections that sound confident and fail on first contact, and forward-looking statements in regulated documents carry explicit disclaimers for the same reason: they are estimates, not facts (J. Crew's FY20 forecast materials on SEC.gov show the standard forward-looking disclaimer that accompanies projection tables). A model that marks those projections UNPROVEN is behaving like a careful reviewer.

One more safeguard: run the review twice with the same inputs and compare tables. Disagreement between runs on a SUPPORTED verdict is a sign the claim is ambiguous, not that the model is unstable. Rewrite the claim until both runs agree.

Making the review part of the log

The conversion should not be a one-off. Two habits keep it cheap. First, store the four blocks in the same record as the decision, so the reviewed version is the version of record. Second, add a review date to the entry, which standard decision log templates already recommend, so each decision gets rechecked against updated metrics rather than being trusted forever (Craft's decision log template and Miro's decision log template both treat status and review as core fields).

For teams logging many decisions, a light pipeline works well: export entries to Markdown, batch them by quarter, and run the same header across the batch. If you would rather not wire a pipeline yourself, Quanta Inference exposes text models through one OpenAI-compatible API key, which is enough to send the header plus entry plus sources and collect the table without managing model providers.

Finally, write the review result back into the entry as a short line: verdict count, date, reviewer. A decision that was checked and one that was not are different artifacts, and the difference is what makes the log worth keeping.

FAQ

FAQ

Why not just ask the model to improve the decision log entry?

Improving is composing, and composing invites the model to fill gaps with plausible-sounding reasoning. When the task is framed as an improvement pass, the output reads well but you cannot separate what came from your files from what the model generated. The check-only header keeps every sentence traceable to a quote, which is the property you actually want from a review.

How many source files should I send with one entry?

Send only the files the evidence block points into: usually one deck, one metrics export, and one call or memo sheet. Adding unrelated files increases the chance of a coincidental match and makes NOT FOUND verdicts less reliable. If the entry cites a source you have not attached, the model should return NOT FOUND, and that is a useful signal that your log points at something you cannot produce.

What do I do when the model returns PARTIAL?

PARTIAL means the source says something weaker or narrower than the claim, so either the claim gets edited down to what the source supports or the source is replaced with a better one. Do not let the model soften the claim for you; it will choose wording that sounds defensible while the underlying gap remains. Fix the entry, then rerun the check on that row.

Can I use this format for decisions that have no deck?

Yes. The deck pointer is just one pointer grammar. Use (memo pN) for written memos, (ticket #N) for issue trackers, or (interview notes row N) for research. What matters is that the pointer names a location a second person could open, not the medium.

How do I know the check is working?

Run the same entry twice and diff the two output tables. Stable verdicts on unchanged inputs mean the format is doing its job. Then plant one deliberate error, such as a wrong cell reference, in a test entry and confirm the model returns NOT FOUND or CONTRADICTED rather than a pass. If it passes the planted error, tighten the quote rule before trusting the pipeline on real entries.

Sources

Sources

  1. Decision log: template, examples, and best practices 2026
  2. Decision log: What it is, why teams use it, and template
  3. Creating an Investor Pitch Deck for Your Startup
  4. Financial Projections Slide: Skip It or Nail It (2026 Guide)
  5. Unleashing the potential of prompt engineering for large ...
  6. A Practitioner's Guide to Prompt Engineering in 2026
  7. 10 Best Practices for Prompt Engineering in 2026
  8. Pitch Deck Examples from 35+ Killer Startups
  9. 34 Inspiring Pitch Deck Examples + Templates
  10. EX-99.1 - SEC.gov
  11. Decision log | Free Template
  12. Decision Log Template
About the author

About the author

Antonio Evans
Antonio Evans

Antonio Evans is the founder of Quanta Intelligence and a fractional CTO who builds HIPAA-ready AI systems for health and life-science companies. Before that he was technical co-founder of FriendsEAT for twenty years, CEO of Socialdraft, and a data engineer at IBM. Antonio lives with his dog Santino in Lisbon, Portugal.

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