Upskill

You are performing an automated skill maintenance pass based on what happened in the current session.

Execute immediately. No preamble, no acknowledgment.

What This Does

Scans the current session transcript to find:

1. Stale skills — skills that were used but contain outdated info (wrong URLs, old versions, missing artifacts, resolved questions still marked open)
2. New skill candidates — repeated multi-step workflows that don't have a skill yet
3. Session index gaps — skills that were used but their session index wasn't updated

Execution

Step 1: Load Session Transcript

# Update this path to match your Claude Code project directory
# Claude Code stores sessions in ~/.claude/projects/<project-slug>/
SESSION_DIR="$HOME/.claude/projects/<your-project-slug>"

LATEST_JSONL=$(ls -t "$SESSION_DIR"/*.jsonl 2>/dev/null | head -1)
echo "Session: $LATEST_JSONL"
wc -l "$LATEST_JSONL"

Extract user messages and assistant tool calls (skill invocations, file writes, URLs generated):

# User messages (what was asked)
jq -r 'select(.type == "user") | select(.message.content | type == "string") | .message.content' "$LATEST_JSONL" 2>/dev/null | head -200

# Skills invoked
jq -r 'select(.type == "assistant") | .message.content[]? | select(.type == "tool_use") | select(.name == "Skill") | .input.skill' "$LATEST_JSONL" 2>/dev/null | sort -u

# Files written or edited
jq -r 'select(.type == "assistant") | .message.content[]? | select(.type == "tool_use") | select(.name == "Write" or .name == "Edit") | .input.file_path' "$LATEST_JSONL" 2>/dev/null | sort -u

# URLs in assistant output
jq -r 'select(.type == "assistant") | .message.content[]? | select(.type == "text") | .text' "$LATEST_JSONL" 2>/dev/null | grep -oP 'https?://[^\s)>"]+' | sort -u

Step 2: Identify Touched Skills

From the signals above, determine which skills were active:

• Skills explicitly invoked via the Skill tool
• Skills whose project files were modified (match file paths to skill project directories)
• Skills whose triggers match topics discussed in user messages

For each identified skill, read its SKILL.md and session index.

Step 3: Spawn Opus Subagent for Analysis

Delegate the diff analysis to Opus. Pass it:

• The extracted session signals (user messages, files touched, URLs generated, skills invoked)
• The current content of each touched skill's SKILL.md
• The current content of each touched skill's session index (if it has one)

Agent({
  description: "Opus upskill analysis",
  model: "opus",
  subagent_type: "general-purpose",
  prompt: `You are analyzing a session transcript to find skill maintenance needed.

DO NOT implement changes. Only produce a structured report.

## Session Signals
{paste extracted signals}

## Existing Skills Touched
{paste each SKILL.md content}

## Session Indexes
{paste each session index}

## Analysis Tasks

### A. Stale Content Detection
For each touched skill, compare its SKILL.md against what actually happened:
- URLs that were generated or changed (new uploads, new pretty-pages)
- Version references that changed (e.g. "v9" → "v10")
- Artifacts created or modified (new files, new scripts, new documents)
- Questions marked "open" that were resolved during the session
- New people, tools, or workflows discovered
- Incorrect or outdated descriptions

### B. Session Index Updates
For each skill with a session index, check if this session should be added.
Draft the session entry with date, session ID, and summary.

### C. New Skill Candidates
Look for multi-step workflows in the session that:
- Took 5+ tool calls to complete
- Don't map to any existing skill
- Would be repeatable in future sessions
- Involve domain-specific knowledge that Claude wouldn't have by default

For each candidate, draft:
- Suggested skill name
- Trigger phrases
- What the skill would contain
- Why it's worth creating (frequency estimate)

### D. Trigger Gaps
Look for user messages that SHOULD have activated a skill but didn't because the trigger list is missing a keyword.

## Output Format

Return EXACTLY this structure:

# Upskill Report

## Skills to Update

### {skill-name}
**Changes needed:**
- {specific change 1 with exact old → new text}
- {specific change 2}

**Session index entry to add:**
\`\`\`json
{exact JSON entry}
\`\`\`

## New Skill Candidates

### {suggested-skill-name}
- **Purpose:** {what it does}
- **Triggers:** {list}
- **Based on:** {what happened in session}
- **Priority:** {Now | Soon | Someday}

## Trigger Updates

### {skill-name}
- **Add trigger:** "{phrase}" — because {reason}

## No Changes Needed
{List any touched skills that are already up to date}
`
})

The Opus agent returns the full report as text.

Step 4: Apply Changes

Using the Opus report, apply each update:

1. Skill file edits — Edit each SKILL.md with the specific changes identified
2. Session index updates — Append new entries to session index files
3. Trigger additions — Add missing triggers to skill frontmatter
4. New skills — For candidates marked "Now", present them for approval before creating

Rules:

• Apply stale-content fixes and session index updates immediately (low risk, high value)
• Present new skill candidates for user approval before creating
• Never delete content from a SKILL.md — only add or update

Step 5: Commit and Report

SESSION_SHORT=$(basename "$LATEST_JSONL" .jsonl | head -c 8)
git add .claude/skills/
git commit -m "upskill: update skills from session $SESSION_SHORT"
git push

Present a summary to the user:

• How many skills were scanned
• How many needed updates (and what changed)
• Any new skill candidates (with approval buttons if applicable)

What This Does NOT Do

• Does not analyze friction or session quality (that's /reflect)
• Does not save session state (that's /pause)
• Does not create slash commands (that's /create-skill)
• Only touches .claude/skills/ — never modifies commands, SOPs, or memory

When to Run

• End of any session that involved project-specific work
• After resolving open questions or creating new artifacts
• When you want Claude to proactively identify skill gaps from what just happened