Local Tools

Local Tools Skill

Environment Variables

No environment variables required. This skill directly accesses system resources.

Prerequisites

macOS

• macOS 10.10 Yosemite or later (for JXA support)
• Calendar.app must be installed (included by default)
• Calendar access permission (user will be prompted on first use)

Windows

• Windows 7 or later
• Microsoft Outlook must be installed and configured
• PowerShell must be available (included by default)
• May require COM access permissions in corporate environments

When to Use This Skill

Use the local-tools skill when you need to:

• Calendar Management - View, create, update, or delete calendar events

Examples of when to use:

• User: "Show me my schedule for tomorrow"
• User: "Create a meeting at 3 PM"
• User: "Search for calendar events containing 'project'"
• User: "Delete tomorrow's meeting"

How It Works

┌──────────┐    Bash/PowerShell    ┌─────────────────────────────────────────────────────────────┐
│  Claude  │──────────────────────▶│  calendar.sh / calendar.ps1                                 │
│          │                       │  ├─ macOS: osascript -l JavaScript (JXA) ──▶ Calendar.app   │
│          │                       │  └─ Windows: PowerShell ──▶ Outlook COM API                 │
└──────────┘                       └─────────────────────────────────────────────────────────────┘

Architecture:

1. CLI Scripts - Platform-specific scripts, no HTTP server needed

   • calendar.sh - Bash script for macOS
   • calendar.ps1 - PowerShell script for Windows

2. Local Calendar Access - Direct access to system calendar

   • macOS: Uses JXA (JavaScript for Automation) to control Calendar.app
   • Windows: Uses PowerShell COM API to control Microsoft Outlook

3. JSON Output - Structured data format for easy parsing

Platform Support

Permissions

macOS

• Requires "Calendar" access permission
• User will be prompted on first use
• Can be managed in: System Settings > Privacy & Security > Calendar

Windows

• Requires Microsoft Outlook to be installed
• May require administrative privileges for COM access

Calendar Operations

IMPORTANT: How to Locate the Script

When you read this SKILL.md file using the Read tool, you receive its absolute path (e.g., /Users/username/.../SKILLs/local-tools/SKILL.md).

To construct the script path:

1. Take the directory of this SKILL.md file
2. Append /scripts/calendar.sh (macOS) or /scripts/calendar.ps1 (Windows)

Example:

# If SKILL.md is at: /Users/username/path/to/SKILLs/local-tools/SKILL.md
# Then the script is: /Users/username/path/to/SKILLs/local-tools/scripts/calendar.sh

bash "/Users/username/path/to/SKILLs/local-tools/scripts/calendar.sh" <operation> [options]

In all examples below, <skill-dir>/scripts/calendar.sh is a placeholder. Replace it with the actual absolute path.

Best Practices for AI Assistant

DO:

• ✅ Execute commands directly without showing trial-and-error process
• ✅ If command fails, inform user about permission issues without showing technical errors
• ✅ Use search command for searching birthdays/anniversaries
• ✅ If no calendar name specified, script will automatically use first available calendar

DON'T:

• ❌ Don't repeatedly try different command combinations
• ❌ Don't show error stacks or technical details to users
• ❌ Don't read script source code to analyze issues
• ❌ Don't ask users for calendar name, use default behavior

Example - Searching for birthdays:

# Correct approach: Search directly, don't trial-and-error
bash "<skill-dir>/scripts/calendar.sh" search --query "birthday"

# If permission error returned, directly tell user:
# "Calendar access permission is required. Please open System Settings > Privacy & Security > Calendar, and authorize Terminal or LobsterAI"

List Events

# List events for next 7 days (default)
bash "<skill-dir>/scripts/calendar.sh" list

# List events for specific date range
bash "<skill-dir>/scripts/calendar.sh" list \
  --start "2026-02-12T00:00:00" \
  --end "2026-02-19T23:59:59"

# List events from specific calendar (macOS)
bash "<skill-dir>/scripts/calendar.sh" list \
  --calendar "Work"

Create Event

# Create a simple event
bash "<skill-dir>/scripts/calendar.sh" create \
  --title "Team Meeting" \
  --start "2026-02-13T14:00:00" \
  --end "2026-02-13T15:00:00"

# Create event with location and notes
bash "<skill-dir>/scripts/calendar.sh" create \
  --title "Client Call" \
  --start "2026-02-14T10:00:00" \
  --end "2026-02-14T11:00:00" \
  --calendar "Work" \
  --location "Conference Room A" \
  --notes "Discuss Q1 roadmap"

Update Event

# Update event title
bash "<skill-dir>/scripts/calendar.sh" update \
  --id "EVENT-ID" \
  --title "Updated Meeting Title"

# Update event time
bash "<skill-dir>/scripts/calendar.sh" update \
  --id "EVENT-ID" \
  --start "2026-02-13T15:00:00" \
  --end "2026-02-13T16:00:00"

Delete Event

bash "<skill-dir>/scripts/calendar.sh" delete \
  --id "EVENT-ID"

Search Events

# Search for events containing keyword (searches ALL calendars)
bash "<skill-dir>/scripts/calendar.sh" search \
  --query "meeting"

# Search in specific calendar only
bash "<skill-dir>/scripts/calendar.sh" search \
  --query "project" \
  --calendar "Work"

Note: When --calendar is not specified, the search operation will look through all available calendars on both macOS and Windows.

Output Format

All commands return JSON with the following structure:

Success Response

{
  "success": true,
  "data": {
    "events": [
      {
        "eventId": "E621F8C4-...",
        "title": "Team Meeting",
        "startTime": "2026-02-13T14:00:00.000Z",
        "endTime": "2026-02-13T15:00:00.000Z",
        "location": "Conference Room",
        "notes": "Weekly sync",
        "calendar": "Work",
        "allDay": false
      }
    ],
    "count": 1
  }
}

Error Response

{
  "success": false,
  "error": {
    "code": "CALENDAR_ACCESS_ERROR",
    "message": "Calendar access permission is required...",
    "recoverable": true,
    "permissionRequired": true
  }
}

Error Codes

Date Format Guidelines

Important: Date Format Guidelines

When using the list command with time ranges:

1. Always use ISO 8601 format: YYYY-MM-DDTHH:mm:ss
2. Use local timezone: Do NOT use UTC or timezone suffixes (like +08:00 or Z)
3. Calculate dates yourself: Do NOT use shell command substitution like $(date ...)
4. Claude should compute dates: Based on current date, calculate target dates directly
5. Examples:
   • Today at midnight: 2026-02-13T00:00:00
   • Today at end of day: 2026-02-13T23:59:59
   • Tomorrow morning: 2026-02-14T09:00:00
   • Next week Monday: 2026-02-16T00:00:00

Why: The script expects local time strings that match your system timezone. Shell substitutions may not execute correctly in all environments.

Common Patterns

Pattern 1: Schedule Management

# User asks: "What meetings do I have today?"
# Claude's approach: Calculate today's date and query full day from 00:00 to 23:59
# IMPORTANT: Claude should replace 2026-02-13 with the actual current date
bash "<skill-dir>/scripts/calendar.sh" list \
  --start "2026-02-13T00:00:00" \
  --end "2026-02-13T23:59:59"

# User asks: "What's on my schedule tomorrow?"
# Claude should calculate tomorrow's date (e.g., if today is 2026-02-13, tomorrow is 2026-02-14)
bash "<skill-dir>/scripts/calendar.sh" list \
  --start "2026-02-14T00:00:00" \
  --end "2026-02-14T23:59:59"

Pattern 2: Meeting Scheduling

# User asks: "Schedule a meeting for tomorrow at 3 PM"
# Claude's approach:
bash "<skill-dir>/scripts/calendar.sh" create \
  --title "Meeting" \
  --start "2026-02-13T15:00:00" \
  --end "2026-02-13T16:00:00" \
  --calendar "Work"

Pattern 3: Event Search

# User asks: "Find all meetings about the project"
# Claude's approach:
bash "<skill-dir>/scripts/calendar.sh" search \
  --query "project" \
  --calendar "Work"

Pattern 4: Availability Check

# User asks: "Am I free tomorrow afternoon?"
# Claude's approach:
# 1. List tomorrow's events
# 2. Analyze time slots
# 3. Report availability
bash "<skill-dir>/scripts/calendar.sh" list \
  --start "2026-02-14T00:00:00" \
  --end "2026-02-14T23:59:59"

Known Behaviors

Time Range Matching

The list command uses interval overlap detection:

• Returns events that have any overlap with the query time range
• Does NOT require events to be fully contained within the range

Examples:

• Query: 2026-02-13 00:00:00 to 23:59:59
• Returns:
  • ✅ Events fully on Feb 13 (e.g., 10:00-11:00)
  • ✅ Multi-day events spanning Feb 13 (e.g., Feb 12 10:00 - Feb 14 10:00)
  • ✅ Events crossing midnight (e.g., Feb 13 23:30 - Feb 14 00:30)
  • ❌ Events entirely before Feb 13 (e.g., Feb 12 10:00-11:00)
  • ❌ Events entirely after Feb 13 (e.g., Feb 14 10:00-11:00)

All-Day Events

• Treated as spanning from 00:00:00 to 23:59:59 on their date(s)
• Multi-day all-day events (e.g., Feb 12-14) will appear when querying any date within that range

Time Precision

• Comparisons use second-level precision
• Milliseconds are ignored in date comparisons

Recurring Events

• Each occurrence is treated as a separate event instance
• The script returns individual occurrences within the queried time range

Best Practices

1. Always Check Before Creating

Before creating an event, list existing events to avoid conflicts:

# First check existing events
bash "<skill-dir>/scripts/calendar.sh" list

# Then create if no conflict
bash "<skill-dir>/scripts/calendar.sh" create ...

2. Use Specific Calendars (macOS)

Specify the calendar to keep events organized:

bash "<skill-dir>/scripts/calendar.sh" create \
  --title "Team Meeting" \
  --calendar "Work" \
  ...

3. Search Before Updating/Deleting

Always search first to get the correct event ID:

# Search to find event ID
bash "<skill-dir>/scripts/calendar.sh" search --query "meeting"

# Then update or delete
bash "<skill-dir>/scripts/calendar.sh" update --id "FOUND-ID" ...

4. Handle Errors Gracefully

Parse the response and handle errors:

result=$(bash "<skill-dir>/scripts/calendar.sh" list)
if echo "$result" | grep -q '"success":true'; then
  # Process events
  events=$(echo "$result" | jq '.data.events')
else
  # Handle error
  error=$(echo "$result" | jq '.error.message')
  echo "Failed: $error"
fi

Limitations

macOS

• Requires macOS 10.10 Yosemite or later (for JXA support)
• Requires Calendar access permission
• Does not support advanced recurring event queries
• Cannot modify recurring event rules

Windows

• Requires Microsoft Outlook to be installed
• Does not support other calendar applications (Windows Calendar, Google Calendar, etc.)
• May require COM access permissions in corporate environments
• Folder enumeration may skip restricted calendars

General

• All dates must be in ISO 8601 format (YYYY-MM-DDTHH:mm:ss)
• Uses local timezone for all operations
• Return values are converted to UTC (ISO 8601 with Z suffix)
• No support for attendees or meeting invitations

Troubleshooting

macOS

Permission Denied:

Error: Calendar access permission is required

Solution: Open System Settings > Privacy & Security > Calendar, authorize Terminal or LobsterAI

Script Not Found:

bash: calendar.sh: No such file or directory

Solution: Ensure you're using the absolute path from SKILL.md's directory + /scripts/calendar.sh

Windows

Outlook Not Found:

Error: Microsoft Outlook is not installed or not accessible

Solution: Install Microsoft Outlook and ensure it's properly configured

PowerShell Execution Policy:

Error: Execution of scripts is disabled on this system

Solution: Run PowerShell as Administrator and execute:

Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

Technical Details

macOS Implementation

JXA (JavaScript for Automation):

• Uses osascript -l JavaScript to execute JXA code
• Controls Calendar.app via Apple Events
• Works on both Intel and Apple Silicon Macs
• Requires user permission for Calendar access

Date Handling:

• Uses BSD date command (macOS native)
• Format: date +%Y-%m-%dT%H:%M:%S (local timezone)
• Relative dates: date -v+7d (7 days from now)

Windows Implementation

PowerShell + COM:

• Uses Outlook COM API via PowerShell
• Requires Outlook to be installed and configured
• Works with all Outlook-compatible calendars

Date Handling:

• Uses PowerShell [DateTime]::Parse() for date parsing
• Automatically handles local timezone

Cross-Platform Consistency

Both implementations:

• Use identical JSON output format
• Support the same operations (list, create, update, delete, search)
• Handle dates in local timezone
• Return UTC timestamps in ISO 8601 format

Related Skills

• imap-smtp-email - For email-based meeting invitations
• scheduled-task - For recurring calendar synchronization