claude-code-skills-reference/references/plugin-troubleshooting.md

Plugin and Skill Troubleshooting

Systematic debugging steps for common plugin and skill installation issues.

Understanding the Architecture First

CRITICAL: Claude Code's plugin system is GitHub-based, not local-file-based.

GitHub Repository (source of truth)
    ↓ (git clone / git pull)
~/.claude/plugins/marketplaces/{marketplace-name}/
    ↓ (claude plugin install)
~/.claude/plugins/cache/{marketplace-name}/{plugin}/{version}/
    ↓ (Claude Code loads)
Active skill in Claude's context

Key insight: Local file changes are NOT visible to claude plugin install until pushed to GitHub.

Common Error 1: "Plugin not found in marketplace"

Error message:

Installing plugin "skill-name@marketplace-name"...
✘ Failed to install plugin: Plugin "skill-name" not found in marketplace "marketplace-name"

Root causes (in order of likelihood):

Cause 1.1: Local changes not pushed to GitHub (MOST COMMON)

Symptoms:

• git status shows modified files or untracked directories
• marketplace.json updated locally but install fails
• All documentation updated but plugin not found

Diagnosis:

# Check if you have uncommitted changes
git status

# Check last commit vs remote
git log origin/main..HEAD

# Verify GitHub has latest marketplace.json
# Open: https://github.com/{owner}/{repo}/blob/main/.claude-plugin/marketplace.json

Solution:

# 1. Commit all changes
git add -A
git commit -m "Release vX.Y.Z: Add {skill-name}"

# 2. Push to GitHub
git push

# 3. Clear local marketplace cache
rm -rf ~/.claude/plugins/cache/{marketplace-name}

# 4. Update marketplace from GitHub
claude plugin marketplace update {marketplace-name}

# 5. Retry installation
claude plugin install {skill-name}@{marketplace-name}

Why this happens: You updated marketplace.json locally, but Claude CLI pulls from GitHub, not your local filesystem.

Cause 1.2: marketplace.json configuration error

Symptoms:

• Git is up-to-date but install still fails
• Other plugins from same marketplace install fine

Diagnosis:

# 1. Check marketplace.json syntax
python3 -m json.tool .claude-plugin/marketplace.json > /dev/null

# 2. Verify plugin entry exists
cat .claude-plugin/marketplace.json | jq '.plugins[] | select(.name == "skill-name")'

# 3. Check spelling matches exactly
# Plugin name in marketplace.json MUST match install command

Common mistakes:

// ❌ Wrong: name mismatch
{
  "name": "macos_cleaner",  // Underscore
  "skills": ["./macos-cleaner"]  // Dash
}

// ✅ Correct: consistent naming
{
  "name": "macos-cleaner",
  "skills": ["./macos-cleaner"]
}

Solution: Fix marketplace.json, then commit and push.

Cause 1.3: Skill directory missing

Symptoms:

• marketplace.json has entry
• Git is up-to-date
• Plugin installs but skills don't load

Diagnosis:

# Check if skill directory exists
ls -la {skill-name}/

# Verify SKILL.md exists
ls -la {skill-name}/SKILL.md

Solution: Ensure skill directory and SKILL.md are committed to git.

Common Error 2: Marketplace cache is stale

Symptoms:

• GitHub has latest changes
• Install finds plugin but gets old version
• Newly added plugins not visible

Diagnosis:

# Check cache timestamp
ls -la ~/.claude/plugins/cache/{marketplace-name}/

# Compare with last git push
git log -1 --format="%ai"

Solution:

# Option 1: Update marketplace cache
claude plugin marketplace update {marketplace-name}

# Option 2: Clear cache and re-fetch
rm -rf ~/.claude/plugins/cache/{marketplace-name}
claude plugin marketplace update {marketplace-name}

Common Error 3: JSON syntax error

Error message:

Error parsing marketplace manifest

Diagnosis:

# Validate JSON syntax
python3 -m json.tool .claude-plugin/marketplace.json

# Check for common issues:
# - Missing commas
# - Trailing commas (in arrays/objects)
# - Unescaped quotes in strings
# - Missing closing braces

Solution: Fix JSON syntax, validate, commit, push.

Systematic Debugging Process

When facing ANY plugin/skill issue, follow this checklist:

Step 1: Verify marketplace registration

# List registered marketplaces
claude plugin marketplace list

# Expected output should include your marketplace

If missing, register:

claude plugin marketplace add https://github.com/{owner}/{repo}

Step 2: Check Git status

# Are there uncommitted changes?
git status

# Is local ahead of remote?
git log origin/main..HEAD

# Push if needed
git push

Step 3: Verify GitHub has latest

# Open in browser or use gh CLI
gh browse .claude-plugin/marketplace.json

# Or check with curl
curl https://raw.githubusercontent.com/{owner}/{repo}/main/.claude-plugin/marketplace.json | jq '.plugins[] | .name'

Step 4: Clear and update cache

# Remove stale cache
rm -rf ~/.claude/plugins/cache/{marketplace-name}

# Re-fetch from GitHub
claude plugin marketplace update {marketplace-name}

Step 5: Validate configuration

# Check marketplace.json is valid JSON
python3 -m json.tool .claude-plugin/marketplace.json > /dev/null && echo "✅ Valid JSON"

# Check plugin entry exists
cat .claude-plugin/marketplace.json | jq '.plugins[] | select(.name == "skill-name")' || echo "❌ Plugin not found"

Step 6: Inspect installation state

# Check if plugin is installed
cat ~/.claude/plugins/installed_plugins.json | jq -r '.plugins | keys[]' | grep "skill-name"

# If installed, check details
cat ~/.claude/plugins/installed_plugins.json | jq '.plugins["skill-name@marketplace-name"]'

# Verify files exist
ls ~/.claude/plugins/cache/{marketplace-name}/{skill-name}/{version}/

Debugging Commands Reference

Purpose	Command
List marketplaces	claude plugin marketplace list
Update marketplace	claude plugin marketplace update {name}
Install plugin	claude plugin install {plugin}@{marketplace}
Uninstall plugin	claude plugin uninstall {plugin}@{marketplace}
Update plugin	claude plugin update {plugin}@{marketplace}
Validate manifest	claude plugin validate {path}
Check installed plugins	cat ~/.claude/plugins/installed_plugins.json | jq '.plugins | keys'
Inspect plugin details	cat ~/.claude/plugins/installed_plugins.json | jq '.plugins["{plugin}@{marketplace}"]'
Clear marketplace cache	rm -rf ~/.claude/plugins/cache/{marketplace-name}
Verify JSON syntax	python3 -m json.tool {file.json}

File Locations

# Marketplace clones (git repositories)
~/.claude/plugins/marketplaces/{marketplace-name}/

# Installed plugin cache
~/.claude/plugins/cache/{marketplace-name}/{plugin-name}/{version}/

# Installation registry
~/.claude/plugins/installed_plugins.json

# Personal skills (not from marketplace)
~/.claude/skills/

# Project-scoped skills (shared with team)
.claude/skills/

Common Pitfalls

Pitfall 1: Confusing local skills with plugin skills

# ❌ Wrong: Copying skill to personal directory doesn't make it installable
cp -r my-skill ~/.claude/skills/my-skill  # Works, but not managed by plugin system

# ✅ Correct: Install via marketplace for version management
claude plugin install my-skill@my-marketplace

Pitfall 2: Forgetting to push after updating marketplace.json

# ❌ Wrong workflow
vim .claude-plugin/marketplace.json  # Add new plugin
git add .claude-plugin/marketplace.json
git commit -m "Add plugin"
# FORGOT TO PUSH!
claude plugin install new-plugin@my-marketplace  # ❌ Fails: not found

# ✅ Correct workflow
vim .claude-plugin/marketplace.json
git add -A
git commit -m "Add new plugin"
git push  # ← CRITICAL STEP
claude plugin marketplace update my-marketplace
claude plugin install new-plugin@my-marketplace  # ✅ Works

Pitfall 3: Expecting instant propagation

# ❌ Wrong expectation
git push  # Push changes
claude plugin install new-plugin@my-marketplace  # ❌ Fails: cache is stale

# ✅ Correct: Update cache first
git push
claude plugin marketplace update my-marketplace  # Fetch latest from GitHub
claude plugin install new-plugin@my-marketplace  # ✅ Works

Pitfall 4: Inconsistent naming

// marketplace.json
{
  "name": "my_plugin",  // Underscore
  "skills": ["./my-plugin"]  // Dash - will cause confusion
}

# User tries to install
claude plugin install my-plugin@marketplace  # ❌ Not found (name has underscore)
claude plugin install my_plugin@marketplace  # ✅ Works, but confusing

Best practice: Use consistent kebab-case for both plugin name and skill directory.

Real-World Example: macos-cleaner Installation Issue

Scenario: After creating macos-cleaner skill and updating all documentation, claude plugin install macos-cleaner@daymade-skills failed with "Plugin not found".

Investigation:

# 1. Check git status
git status
# Output: 16 modified/untracked files

# 2. Check marketplace cache
ls -la ~/.claude/plugins/cache/daymade-skills/
# Output: Last modified Dec 20 (weeks old!)

# 3. Check GitHub
# marketplace.json on GitHub: version 1.20.0 (old)
# Local marketplace.json: version 1.21.0 (new)

Root cause: Local changes weren't pushed to GitHub. CLI was pulling from GitHub, not local files.

Solution:

# 1. Commit and push
git add -A
git commit -m "Release v1.21.0: Add macos-cleaner"
git push

# 2. Update marketplace
claude plugin marketplace update daymade-skills

# 3. Install
claude plugin install macos-cleaner@daymade-skills
# ✔ Successfully installed plugin: macos-cleaner@daymade-skills

Verification:

cat ~/.claude/plugins/installed_plugins.json | jq '.plugins["macos-cleaner@daymade-skills"]'
# Output: Installation details with correct version

ls ~/.claude/plugins/cache/daymade-skills/macos-cleaner/1.0.0/
# Output: All skill files present

Lesson: Always remember the GitHub-based architecture. Local changes are invisible until pushed.

Advanced: Manual Cache Inspection

If automated commands don't reveal the issue, manually inspect:

# 1. Check marketplace clone
cat ~/.claude/plugins/marketplaces/{marketplace-name}/.claude-plugin/marketplace.json | jq '.metadata.version'

# 2. Check what's in cache
ls -R ~/.claude/plugins/cache/{marketplace-name}/

# 3. Compare with GitHub
curl -s https://raw.githubusercontent.com/{owner}/{repo}/main/.claude-plugin/marketplace.json | jq '.metadata.version'

# 4. Check installation record
cat ~/.claude/plugins/installed_plugins.json | jq '.plugins' | grep -i "{skill-name}"

When All Else Fails

1. Complete cache reset:

   rm -rf ~/.claude/plugins/cache/*
   claude plugin marketplace update {marketplace-name}
   

2. Re-register marketplace:

   # Remove marketplace
   # (No direct command, manual edit ~/.claude/plugins/known_marketplaces.json)
   
   # Re-add
   claude plugin marketplace add https://github.com/{owner}/{repo}
   

3. Check Claude Code version:

   claude --version
   # Plugins require Claude Code v2.0.12+
   

4. Enable verbose logging (if available):

   CLAUDE_DEBUG=1 claude plugin install {plugin}@{marketplace}
   

Getting Help

If you're still stuck:

1. Check GitHub issues: https://github.com/anthropics/claude-code/issues
2. Verify marketplace.json: Run claude plugin validate .claude-plugin/marketplace.json
3. Compare with working marketplace: Study anthropic's official marketplace structure
4. Document your debugging: Include output from all diagnostic commands above