weatherreporter/docs/internal/prompt-input.md

Prompt Input Internals

This document describes the implemented prompt input package boundary.

Purpose

internal/promptinput converts a structured briefing package into the data_package JSON file passed to scriptorium prompts.

Inputs and Outputs

Input:

• briefing.Package containing Daily-family, 3-Day Outlook, Weekend Outlook, or Storm Report content

Output:

• promptinput.Package JSON with report metadata, briefing content, source warnings, RunID, and a Recent Changes section.

Boundaries

• This package owns the prompt input schema and required-field validation.
• It does not fetch weather data, compute forecast summaries, compare prior snapshots, or invoke scriptorium.

Behavior

• promptinput.Build copies report metadata from the briefing package.
• promptinput.Validate rejects missing or inconsistent required fields before render preflight.
• promptinput.Save writes JSON atomically where practical.
• Recent Changes is present as an items list. It is empty when no prior comparable snapshot exists or no meaningful changes are detected.

Failure Behavior

Validation errors name the missing or inconsistent field. Save failures include the filesystem operation and path context.

Tests

Inspect:

• internal/promptinput/package_test.go
• internal/changes/daily_test.go
• internal/app/app_test.go

Invariants

• Prompt input data remains structured JSON.
• Briefing metadata and top-level report metadata must agree.
• Recent Changes is not inferred from rendered report text.