PromptSharp › Daily briefs › Finance › October 6, 2026

Finance prompt of the day

October 6, 2026 · for Investment banking, sales & trading, equity research, FP&A. One sharp, copy-paste prompt — free, every weekday.

You are a valuation reviewer interrogating a WACC build I paste: [COMPONENTS: risk-free, ERP, beta, cost of debt, tax rate, capital-structure weights]. Produce:
1. A COMPONENT-BY-COMPONENT challenge: for each input, is the source/convention defensible, what range is reasonable, and how sensitive is WACC to it. Where a figure is not provided, write "not provided" — do not supply a market number from memory.
2. A CONSISTENCY check: does beta match the assumed capital structure (relever?), is the risk-free tenor matched to cash-flow horizon and currency, is the tax rate marginal vs effective.
3. A SENSITIVITY read: the WACC range across reasonable inputs and which single input moves it most.
4. The 3 assumptions a PM/VP will push on first, and my best answer for each.

Rules: Do not invent, estimate, or extrapolate any figure — if a number is not in what I give you, write "not provided" and flag it. Mark every claim I should verify externally before relying on it. Never use, infer, or request material non-public information (MNPI) or client-confidential data.

What changed for Finance

How to run “WACC build interrogation”, step by step

The situation this prompt is built for: Your discount rate drives the whole valuation and you want every component of the WACC challenged before you trust it. Below is exactly what to feed it and what comes back — no model-specific tricks, it runs the same in any chat AI.

What each placeholder does

Demo profile for the example fills: an equity research associate on a mid-cap sector coverage team, working in Excel, a chat AI model, and your firm's data terminal. Swap in your own context — or save it once at /profile and copied prompts arrive pre-filled.

• [COMPONENTS: risk-free, ERP, beta, cost of debt, tax rate, capital-structure weights] — this is the input the whole output quality hangs on. Each part narrows the answer: components: risk-free; erp; beta; cost of debt; tax rate; capital-structure weights. Demo fill: your own components: risk-free, erp, beta, cost of debt, tax rate, capital-structure weights — one or two concrete lines beats a paragraph of vague context. Leave it vague and the model pads with boilerplate; make it concrete and every section downstream sharpens.

What the model hands back

The prompt forces a fixed deliverable shape, so you get a document, not a ramble:

1. A COMPONENT-BY-COMPONENT challenge: for each input, is the source/convention defensible, what range is reasonable, and how sensitive is WACC to it. Where a figure is not provided, write "not provided" — do not supply a market number from memory.
2. A CONSISTENCY check: does beta match the assumed capital structure (relever?), is the risk-free tenor matched to cash-flow horizon and currency, is the tax rate marginal vs effective.
3. A SENSITIVITY read: the WACC range across reasonable inputs and which single input moves it most.
4. The 3 assumptions a PM/VP will push on first, and my best answer for each.

Why this structure works

WACC is precision theater when unlabeled guesses are ranked like measurements; forcing each component's defensibility, an internal-consistency check, and a sensitivity range replaces a false-precision point estimate with a defensible band.

On Pro, the WACC conventions arrive pre-set to your firm's house method (which ERP source, relevering approach) from the profile you set once.

When to use it — and when not to

Reach for it when

• Your discount rate drives the whole valuation and you want every component of the WACC challenged before you trust it.
• You can actually supply the inputs it asks for ([COMPONENTS: risk-free, ERP, beta, cost of debt, tax rate, capital-structure weights]) — this prompt is an amplifier for real context, not a substitute for it.
• You need the output in a shape you can forward as-is — the fixed structure above is the point.

Skip it when

• You don’t yet have the source material — the prompt is built to refuse to fake it. Its own guardrail: “Do not invent, estimate, or extrapolate any figure — if a number is not in what I give you, write "not provided" and flag it.” With nothing to work from, you’ll get a list of “not provided” flags, which is honest but not useful. Collect the inputs first.
• The task is genuinely one sentence long — a structured prompt earns its overhead when the output has parts. For quick one-off questions, just ask.

Adapting today’s prompt for adjacent roles

“WACC build interrogation” sits in the Financial Analysis & Modeling lane of the finance pool. If your seat is one desk over, these are the same craft-move rebuilt for the neighbouring workflow — pulled from the same curated pool, each free in full at its permalink:

You are an M&A analyst running a FIRST-PASS accretion/dilution check. I will give acquirer and target [EPS, net income, shares, offer price, % cash vs stock, expected…

You are a trading coach running a POST-MORTEM on a closed trade. I will give the thesis, entry, sizing, management, exit, and outcome. Produce: 1. A verdict on PROCESS…

You are a buy-side analyst assessing the moat of [COMPANY]. I will paste business facts. Produce: 1. A moat VERDICT: none / narrow / wide, with the specific source(s)…

Common failure modes (and the fixes)

• Failure: letting the model drift past the prompt’s own guardrail — “Do not invent, estimate, or extrapolate any figure — if a number is not in what I give you, write "not provided" and flag it.” Fix: keep that line in when you edit the prompt; it exists because this is exactly where outputs go wrong without it.
• Failure: letting the model drift past the prompt’s own guardrail — “Mark every claim I should verify externally before relying on it.” Fix: keep that line in when you edit the prompt; it exists because this is exactly where outputs go wrong without it.
• Failure: letting the model drift past the prompt’s own guardrail — “Never use, infer, or request material non-public information (MNPI) or client-confidential data.” Fix: keep that line in when you edit the prompt; it exists because this is exactly where outputs go wrong without it.
• Failure: filling [COMPONENTS: risk-free, ERP, beta, cost of debt, tax rate, capital-structure weights] with a vague summary. The output can only be as specific as this input — generic context in, generic deliverable out. Fix: paste raw specifics (real names, real numbers, real constraints), then trim the model’s output, not your input.
• Failure: accepting the first pass. Fix: reply with one line — “now cut everything that is generic to any company and keep only what is specific to mine” — the cheapest quality doubling available.

Where AI is landing for investment banking right now

Context for today’s prompt, from the same screened sources the daily brief reads. Our read, with sources linked — the pattern across items like these is consistent: the professionals getting leverage from AI are the ones feeding it real working context, which is exactly the muscle today’s prompt trains.

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Quick answers

Is “WACC build interrogation” free to use?

Yes — every weekday issue of the PromptSharp Finance publishes one full pool prompt free on the web, and it stays free in the archive. Pro is the daily full prompt set, personalization, and MCP delivery — not a paywall on this page.

Which AI model does this prompt work with?

Any of them. Every PromptSharp prompt is model-agnostic plain text — ChatGPT, Claude, Gemini, Copilot, or a local model. No plugins, no custom GPTs; paste and run.

How is the finance prompt of the day chosen?

Deterministic rotation over the curated finance pool — currently 80 prompts across 5 sections — the same single source the paid brief reads. Same date, same prompt: the archive never silently changes under you.

What goes in the [BRACKETED] placeholders?

Your context — the walkthrough above covers each one. The short rule: the more concrete the fill (real names, numbers, constraints), the sharper the output. Save your details once at /profile and web copies arrive pre-filled.

How do I get this in my inbox instead?

The capture form above. The PromptSharp Finance email edition lands every weekday morning, plus a Sunday roundup; the web issue stays free here either way.

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