6. Grounded presentation and booking

Search results are structured application data. A chat model may make them pleasant to read, but it must not invent a hotel, alter a price, or claim a booking that has not happened.

Prime an isolated presentation stage

PresentStep shares the present memory namespace with its judge. On entry it erases old presentation history; on crossing it creates a synthetic request:

protected override async onEnter(): Promise<void> {
  this.eraseMemory();
}

public override onCrossing(): MessageTypes {
  return new HumanMessageEx(this, 'Present the current matching hotels.');
}

The prompt injects the exact hotelFound array. Intake history stays in the separate intake namespace.

Capture the draft before releasing it

When the chat model produces ordinary text, onResponse() saves it and routes to the judge instead of returning it to the user:

public override async onResponse(
  llmResult: string | object,
): Promise<LastResponseType> {
  const draft =
    typeof llmResult === 'string' ? llmResult : JSON.stringify(llmResult);
  this.saveState({ draft });
  return go(PresentationJudgeStep);
}

The durable cursor moves to PresentationJudgeStep within the same turn. Its facts contain the draft, saved hotels, and criteria.

Judge bounded properties

The judge asks whether the draft is grounded and scores completeness and clarity. Application code sets the release threshold:

const accepted =
  answers.grounded.noul >= 0.85 &&
  answers.completeness.score >= 1.5 &&
  answers.completeness.confidence >= 0.75 &&
  answers.clarity.score >= 1.5 &&
  answers.clarity.confidence >= 0.75;

return directTo(
  PresentStep,
  accepted ? draft : CriteriaHelper.renderHotelResults(hotels),
);

directTo(PresentStep, content) moves the durable cursor back to the booking stage, returns exact content, and ends the turn without another model call. A rejected draft never reaches the customer.

Deterministic fallback rendering

CriteriaHelper.renderHotelResults() builds a numbered list directly from the saved array. PresentationJudgeStep.onDecisionError() returns that same list when Jev is unavailable. This boundary fails closed with respect to generated prose: only a reviewed draft or code-rendered results can be shown.

The renderer does not make the model’s prose “more likely” to be correct. It is a separate, always-grounded output path.

Revision returns to the owner graph

PresentStep exposes a revise_search tool. It forwards the latest request to RouterStep when available:

const message = this.getLastMessage();
return message
  ? go('RouterStep').withMessage(message)
  : go('RouterStep');

The same routing and collector validation used during intake therefore handle a later budget or date correction. Search results are replaced only after a new validated search.

Validate the terminal selection

The booking tool accepts a name but resolves either an exact normalized name or a one-based number against hotelFound:

const hotels = this.getState<SearchHotelEntry[]>('hotelFound') ?? [];
const selected = resolveHotel(args.hotelName, hotels);
if (!selected) {
  return stay('Choose a hotel name or number from the current result list.');
}

const confirmationNumber = Math.floor(100000 + Math.random() * 900000);
this.saveState({
  selectedHotel: selected.hotelName,
  confirmationNumber,
});
return finish(
  `${selected.hotelName} is booked with confirmation #${confirmationNumber}. Thank you for choosing Hilton.`,
);

The model cannot select an arbitrary hotel by inventing an ID. finish(...) returns the exact confirmation, marks the session completed, keeps the current cursor, and makes no follow-up model call.

In production, replace the random number with an idempotent backend reservation write and persist the external operation ID before returning the confirmation.

Common mistakes

• Showing the draft before review. Save it and route; release only the judge’s selected output.
• Using another model as the fallback. The outage path should depend only on saved application data.
• Letting the model book by free text. Resolve against the current result set in code.
• Returning to intake without the revision message. Forward it when the router must classify it.
• Calling finish() before the durable side effect succeeds. Completion belongs after the backend commit.

Next

7. Fallbacks and two-tier testing tests every decision boundary without providers, then separates that evidence from a real OpenAI-and-Jev replay.