Prompt Contracts

Choose the Output Structure Early

Structure organizes information and directs attention. Markdown, JSON, and XML work well because they're information-dense formats heavily represented in training data. Pick the shape before details compete for attention.

# Task: Draft an architecture decision record for moving report generation from synchronous requests to asynchronous jobs.

## Context- Enterprise reports time out during peak usage.- Customers expect downloadable reports and email notifications.- Support needs explainable status for delayed jobs.

## Constraints- Preserve the existing API contract during rollout.- Keep audit logs for every generated report.- Support rollback without losing in-progress work.

## Options1. Queue-backed async jobs2. Scheduled batch generation3. Keep synchronous flow and optimize queries

## Return- Recommendation with trade-offs- Rollout and rollback plan- Observability gaps and validation criteria

1Decision frame

Sets the artifact as an architecture decision, not an implementation dump.

2Context + constraints

Separates why the decision exists from the non-negotiable boundaries.

3Options

Forces trade-off analysis before recommending an approach.

4Execution + validation

Connects the decision to rollout, observability, and success criteria.

The structure makes the decision reviewable: why this matters, what cannot break, which options were considered, and how success will be verified.

Add Constraints as Guardrails

Without constraints, the model fills gaps with assumptions. Define boundaries explicitly.

Unconstrained

Move file processing to background jobs.

Constrained

Design a migration plan for moving file processing from synchronous API requests to asynchronous jobs.

Constraints:
- Preserve the current API response contract during rollout.
- No user-visible regression for upload progress or error recovery.
- Preserve audit logs and idempotency guarantees.
- No schema change without a backfill and rollback plan.

Return affected systems, migration phases, risks, evidence needed, and decisions that require human approval.

1Decision

Frames the work as a migration plan instead of a vague refactor.

2Boundaries

Protects customer experience, contracts, auditability, and rollback.

3Contract

Requires evidence and open decisions instead of pretending the plan is complete.

The unconstrained version invites the agent to jump into implementation. The constrained version defines the operational envelope before code exists.

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