decomposing-tasks

Task Decomposition

Create an execution-ready plan from a feature specification with automatic phase grouping based on file dependencies.

When to use: After completing a feature spec with /spectacular:spec, to create an implementation plan.

Announce: "I'm using the Task Decomposition skill to create an execution plan."

Input

User will provide: /spectacular:plan {spec-path}

Example: /spectacular:plan @specs/a1b2c3-magic-link-auth/spec.md

Where a1b2c3 is the runId and magic-link-auth is the feature slug.

Multi-Repo Support

Detecting Multi-Repo Mode

Check if workspace contains multiple repos:

# Detect workspace mode (same as writing-specs skill)
REPO_COUNT=$(find . -maxdepth 2 -name ".git" -type d 2>/dev/null | wc -l | tr -d ' ')
if [ "$REPO_COUNT" -gt 1 ]; then
  echo "Multi-repo workspace detected ($REPO_COUNT repos)"
  WORKSPACE_MODE="multi-repo"
  # List detected repos
  REPOS=$(find . -maxdepth 2 -name ".git" -type d | xargs -I{} dirname {} | sed 's|^\./||' | tr '\n' ' ')
  echo "Available repos: $REPOS"
else
  echo "Single-repo mode"
  WORKSPACE_MODE="single-repo"
fi

Multi-Repo Task Format

In multi-repo mode, each task MUST specify which repo it belongs to:

### Task 1.1: Add user_preferences table

**Repo**: backend
**Files**:
- prisma/schema.prisma
- prisma/migrations/*

**Constitution**: @backend/docs/constitutions/current/

Single-Repo Task Format (unchanged)

### Task 1.1: Add user_preferences table

**Files**:
- prisma/schema.prisma
- prisma/migrations/*

**Constitution**: @docs/constitutions/current/

Full Workflow

Step 0: Extract Run ID and Feature Slug from Spec

First action: Read the spec and extract the RUN_ID from frontmatter and determine the spec directory.

# Extract runId from spec frontmatter
RUN_ID=$(grep "^runId:" {spec-path} | awk '{print $2}')
echo "RUN_ID: $RUN_ID"

# Extract feature slug from the spec path
# Path pattern: .../specs/{runId}-{feature-slug}/spec.md
# Use sed to extract directory name without nested command substitution
SPEC_PATH="{spec-path}"
DIR_NAME=$(echo "$SPEC_PATH" | sed 's|^.*specs/||; s|/spec.md$||')
FEATURE_SLUG=$(echo "$DIR_NAME" | sed "s/^${RUN_ID}-//")
echo "FEATURE_SLUG: $FEATURE_SLUG"