# Comet Design

Comet Phase 2: Deep Design.

- Repository: https://github.com/rpamis/comet (3263 stars)
- Category: Design
- License: MIT
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add rpamis/comet --skill comet-design -g -a claude-code -y`
Codex: `npx skills add rpamis/comet --skill comet-design -g -a codex -y`
Cursor: `npx skills add rpamis/comet --skill comet-design -g -a cursor -y`
Gemini CLI: `npx skills add rpamis/comet --skill comet-design -g -a gemini-cli -y`

## Description

Comet Phase 2: Deep Design. Invoke with /comet-design. Produce Design Doc and delta spec through brainstorming.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Comet Phase 2: Deep Design (Design)

## Prerequisites

- Active change exists (proposal.md, design.md, tasks.md)
- No Design Doc (no corresponding file under `docs/superpowers/specs/`)

## Steps

### 0. Entry State Verification (Entry Check)

Execute entry verification:

```bash
COMET_ENV="${COMET_ENV:-$(find . "$HOME"/.*/skills "$HOME/.config" "$HOME/.gemini" -path '*/comet/scripts/comet-env.sh' -type f -print -quit 2>/dev/null)}"
if [ -z "$COMET_ENV" ]; then
  echo "ERROR: comet-env.sh not found. Ensure the comet skill is installed." >&2
  return 1
fi
. "$COMET_ENV"
"$COMET_BASH" "$COMET_STATE" check <name> design
```

Proceed to Step 1 after verification passes. The script outputs specific failure reasons when verification fails.

**Idempotency**: All design phase operations can be safely re-executed. If `handoff_context` and `handoff_hash` already exist, confirm they match current artifacts before deciding whether to regenerate.

### 1a. Generate OpenSpec → Superpowers Handoff Package

**Must be generated by script. Agent writing summaries on the fly is not allowed.**

```bash
"$COMET_BASH" "$COMET_HANDOFF" <change-name> design --write
```

The script reads the change `.comet.yaml` `context_compression` snapshot, then generates and records the matching handoff package.

Default `context_compression: off` generates:

```
openspec/changes/<name>/.comet/handoff/design-context.json
openspec/changes/<name>/.comet/handoff/design-context.md
```

Beta mode (`context_compression: beta` in project `.comet/config.yaml`, snapshotted into `.comet.yaml` when the change is created) generates:

```
openspec/changes/<name>/.comet/handoff/spec-context.json
openspec/changes/<name>/.comet/handoff/spec-context.md
```

And writes to `.comet.yaml`:

```yaml
handoff_context: openspec/changes/<name>/.comet/handoff/design-context.json
handoff_hash: <sha256>
```

The rest: https://github.com/rpamis/comet/blob/HEAD/eval/local/skills/benchmarks/039-release/comet-classic-039-design/SKILL.md