Graphical software
The interface owns the route1User
2Find invoice
3Approve
4Outcome
The person learns the product's language and follows its sequence.
An interactive product thesis
Don't shoot the messenger.
Why grammar is reshaping product development.
When software can interpret language and take action, product teams must design the vocabulary, rules, and evidence behind every outcome.
NounInvoice
VerbApprove
AdjectiveVerified
RuleManager review
Approve the verified invoice after manager review.
The problem
When an agent gets it wrong, we blame the model.
But the model is the messenger. It acted on a sentence whose words nobody had defined.
Approve
Verb
Approve how far?
Mark it approved, post it to the ledger, release the payment, tell the supplier? Nothing said where the action stops.
the verified
Adjective
Verified against what?
The purchase order, the supplier record, the amount, all three? The model has to invent the test it is being judged on.
invoice
Noun
Nothing to guess.
The schema names its fields and what it links to, so the model can look this one up instead of inferring it.
above €10,000
Rule
Gross, net, or converted?
Before or after tax, and at which day’s exchange rate? The threshold sat in a document the agent could not read.
Six parts · this failure came from three
Nouns
Verbs
Adjectives
Adverbs
Sentences
Rules
Three of four words were never written down. No amount of fixing the model writes them.
The shift
Graphical software gives people paths. Agentic software constructs them.
The centre of composition moves from screens and clicks into runtime interpretation.
Agentic software
Intent creates the routeUser intent
Retrieve
Verify
Route
Approve
The model translates human language into the product's executable vocabulary.
The vocabulary
Explore one part of the grammar at a time.
Tap a word type to change the visual and explanation
Finance agent approves the verified invoice after manager review.
Objects
Nouns define what exists.
Compose a capability
A product sentence becomes an executable capability.
Choose an action, a condition, and an object. The system must make the resulting sentence safe and real.
Approve the verified invoice after manager review.
The model composes the sentence. Code enforces the approval rule.
The system
Five actors share responsibility for one outcome.
This is not a five-step pipeline. Four actors shape the approval sentence, while the trace observes the whole interaction.
Select an actor for its role
Shared objectApprove verified invoice after manager review
User
Intent and authority
Model
Interpretation
Harness
Tools and boundaries
Code
Validation and execution
Trace observes every transition
Request · evidence · decision · tool · outcome
UserDefines the desired outcome
The user asks to approve verified supplier invoices while preserving manager review above €10,000.
A consequential sentence
Simple words can hide complex policy.
User requestApprove verified supplier invoices automatically, but ask a finance manager to review any invoice above €10,000.
Approve
Executable capability selected by the model and performed by code.
VerbInvoice
Business object defined by the product schema.
NounVerified
Policy word that must resolve into testable conditions.
AdjectiveAbove €10,000
Deterministic threshold that code should calculate.
ConstraintManager review
Authority boundary where the harness must pause.
RuleThe product discipline
Design the language of action.
A capable model needs a clear vocabulary, enforceable rules, and evidence from every sentence it constructs.
1
NounsDefine what exists.
2
VerbsInventory every action.
3
AdjectivesSpecify consequential conditions.
4
ResponsibilitySeparate judgment and enforcement.
5
TracesInspect intent to consequence.
6
EvaluationImprove grammar from evidence.
The interface tells us what a person can do. The trace tells us what an agent did. Grammar design connects the two.