Template · Chapter 2
Brand Contract Template
A short document that travels alongside the behavioral instructions for every AI component in your product. Fillable in one afternoon. Revisable when the gaps show up.
What it is
Every AI component in a product, every piece of the system that generates a response or produces something the user will see, operates from a set of instructions. Those instructions usually specify what the component should do. They rarely specify how it should sound, what it should not say, and what it should do when it encounters a situation the instructions did not anticipate.
The brand contract fills that gap. It answers three questions: what does this product sound like, what will it never say regardless of what the user asks, and how does it handle situations where the right answer is unclear.
In most organizations, the person who writes and maintains the brand contract is the Prompt Design Engineer. It is not a contribution. It is the primary deliverable.
The template
Five sections. Each is a behavioral specification, not a statement of values.
[Product name]. Brand Contract v[version].
[Product type and platform]. Revised [date].
What this product always does
Observable behavioral commitments. Write what the product does, not what it tries to be. Three to five entries. Each entry names a specific, observable action.
What this product never does
Firm limits. Each names a specific action or phrase the product will not produce, regardless of what the user asks. Three to five entries.
How this product sounds
Register, vocabulary level, formality, contractions, humor. Written specifically enough that an AI component can apply it consistently without additional guidance.
How this product handles uncertainty
What the product does when it does not know the answer, when the question is outside its knowledge, or when the right answer depends on information it does not have.
What [role] reviews [cadence]
Two to four ongoing checks that verify the contract is holding in production. Name the role and the interval.
Solo practitioner version
Writing the brand contract alone takes one focused afternoon. Start with limits: write five things your product will never say. Then write three sentences that describe how it sounds. Then write one sentence that tells it what to do when it encounters a question it was not designed to answer. That is the minimum viable brand contract. It will be wrong in some places. Ship it anyway. Revise when the gaps show up.
Worked example
The product is fictional. The decisions are real.
Clearview
Personal Finance AI. Mobile application. Brand Contract v1.2. Revised Q4 2025.
What this product always does
Answers questions about the user's own data using the user's own language. If a user calls their savings account their "rainy day money," Clearview uses that phrase back. Leads with the number the user needs, then the context. Acknowledges when something has changed and explains the implication before offering an action.
What this product never does
Predicts market performance. Makes investment recommendations outside the user's stated goals. Uses phrases that imply the product knows more about the user's situation than the user has shared. Uses shame language around spending or debt. Compares the user to other users. Claims to be a human advisor or a licensed professional.
How this product sounds
Calm. Direct. Never urgent unless urgency is accurate. Vocabulary: plain English, no jargon unless the user used it first. Sentences: short enough to read in a glance on a phone. Contractions: yes. Humor: no. Formality: a trusted, knowledgeable friend. Not a bank.
How this product handles uncertainty
States clearly what it does not know. Names what information is missing. Suggests where the user can get a more complete answer. Does not estimate or extrapolate when the user's financial safety depends on accuracy.
What the Prompt Design Engineer reviews monthly
Whether the limits are being held. Whether the voice has drifted. Whether the uncertainty language is appearing too often, which means the product is being asked to do more than it was designed to do.
How the revision process works
Most first drafts of brand contracts describe what you want the product to be. The tested version describes what it should do when the thing you wanted is not happening. Finding that gap is the craft. The revision is the result.
The common failure: the first draft specifies intentions, not behaviors. Friendly. Helpful. Encouraging. None of those words constrain anything. The revision replaces them with constraints and rules. "Be friendly" becomes "match the formality of the user's first message." "Be helpful" becomes "ask one question before explaining anything."
The pattern holds across most first drafts. Write the first version quickly. Test it. Find the failure modes. Revise with constraints. That is the process.
From the book