## Purpose

Canonical specification for queued-image-refetch-with-backoff requirements synced from OpenSpec change deltas.

## Requirements

### Requirement: Latest-30 queue construction
The refetch-images command SHALL enqueue up to the latest 30 news items for processing in batch mode and support targeted single-article mode when permalink targeting is provided.

#### Scenario: Queue population
- **WHEN** refetch-images is started without a permalink target
- **THEN** the command loads recent news items
- **AND** enqueues at most 30 items ordered from newest to oldest

#### Scenario: Targeted permalink mode
- **WHEN** refetch-images is started with a valid permalink target
- **THEN** the command enqueues only the resolved article
- **AND** bypasses latest-30 queue expansion

### Requirement: Sequential processing
The image refetch queue SHALL be processed one item at a time.

#### Scenario: Single-item worker behavior
- **WHEN** queue processing runs
- **THEN** only one queued item is processed concurrently
- **AND** next item starts only after current item completes/fails

### Requirement: Exponential backoff on transient failures
The queue processor SHALL retry transient image-provider failures using exponential backoff.

#### Scenario: Rate-limited provider response
- **WHEN** provider call returns rate-limit or transient error
- **THEN** command retries with exponential delay between attempts
- **AND** stops retrying after configured max attempts

### Requirement: Progress and completion reporting
The command SHALL emit operator-readable progress and final summary output.

#### Scenario: Queue progress output
- **WHEN** queue processing is in progress
- **THEN** the command prints per-item progress (processed/succeeded/failed)
- **AND** prints final totals on completion