pr-description-crafter

name	pr-description-crafter
description	Explains how Sylph composes PR descriptions — the 4-section template, the fallback ladder when Crow V4 continuity or W2 cluster data is missing, and how to override the default template via PULL_REQUEST_TEMPLATE.md.
allowed-tools	Read

pr-description-crafter

The 4-section template

## What changed     — commit subjects, with short SHAs
## Why              — session intent (Crow V4) or inferred from commits
## How it was verified — observed test runs, or "inspection only"
## Rollback plan    — `git revert --no-commit <shas>` template

Fallback ladder

Sylph produces the best description it can from whatever signals are present:

1. Full signal (Crow V4 installed + W2 active + commits present) → every section populated from distinct sources. Ideal state.
2. No Crow V4 (most common today — Crow is Phase-1 shipping) → "Why" block notes the missing data and falls back to commit-subject synthesis.
3. No W2 cluster (user hasn't adopted auto-orchestration) → Title uses the last commit's subject; body uses commit list only.
4. No commits (rare — only if the branch has just been created) → Refuse; /sylph:pr aborts with a hint to commit first.

Overriding

If the repo has a GitHub .github/PULL_REQUEST_TEMPLATE.md, Sylph honors it by appending the four Sylph sections below the template. Developers who want Sylph's sections to replace the template should delete the template file; developers who want Sylph to defer entirely can set:

# .sylph/config.yaml
pr_description:
  mode: template-only    # "template-only" | "append" (default) | "sylph-only"

[Not yet implemented — roadmap.]

When to invoke this skill

• A developer asks "can I customize the PR body?"
• A PR description looks wrong and the developer wants to understand which signal was missing.
• Debugging why an Opus call for pr-description-crafter produced a thin body.

Cost notes

The pr-description-crafter agent is Opus-tier. Each PR open costs ~1 Opus call (typically 2k-6k input tokens, 500-1500 output). If Pech signals budget pressure via pech.budget.threshold.crossed, Sylph degrades to Sonnet (produces a serviceable but terser description) and tags the PR body with a *(budget-degraded)* marker.