Agent Skills: Google Master

Google Master

This is NOT a user-facing skill. It's a shared resource library referenced by all Google integration skills.

Purpose

Provides shared resources to eliminate duplication across:

• gmail - Email operations (read, send, reply, forward)
• google-docs - Document operations (read, write, create, export)
• google-sheets - Spreadsheet operations (read, write, append)
• google-calendar - Calendar operations (events, availability, scheduling)

Instead of loading this skill, users directly invoke the specific skill they need above.

Architecture: DRY Principle

Problem solved: Google skills would have duplicated content (OAuth setup, credentials management, error handling, API patterns).

Solution: Extract shared content into google-master/references/ and google-master/scripts/, then reference from each skill.

Result:

• Single OAuth flow for all Google services
• One credentials source (.env file with GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET, GOOGLE_PROJECT_ID)
• One unified token with all scopes
• Consistent error handling across skills

Shared Resources

All Google skills reference these resources (progressive disclosure).

scripts/

Authentication & Configuration

google_auth.py - Unified OAuth for all Google services

python google_auth.py --check [--service SERVICE] [--json]
python google_auth.py --login [--service SERVICE]
python google_auth.py --logout
python google_auth.py --status

| Argument | Required | Default | Description | |----------|----------|---------|-------------| | --check | No | - | Check if authenticated and ready | | --login | No | - | Initiate OAuth login flow | | --logout | No | - | Remove stored token | | --status | No | - | Show detailed auth status | | --service | No | all | Specific service: gmail, docs, sheets, calendar, or all | | --json | No | False | Output as JSON |

Exit codes:

• 0 = configured and ready
• 1 = needs login (credentials exist but not authenticated)
• 2 = not configured (missing credentials or dependencies)

When to Use: Run this FIRST before any Google operation. Called automatically by individual skills.

check_google_config.py - Pre-flight validation

python check_google_config.py [--json]

| Argument | Required | Default | Description | |----------|----------|---------|-------------| | --json | No | False | Output structured JSON for AI consumption |

When to Use: Quick check if Google integration is configured. Use for diagnostics.

references/

setup-guide.md - Complete setup wizard

• Creating Google Cloud project
• Enabling APIs (Gmail, Docs, Sheets, Calendar)
• Creating OAuth 2.0 credentials
• Adding credentials to .env file
• First-time authentication flow

error-handling.md - Troubleshooting

• Common errors and solutions
• HTTP error codes (401, 403, 404)
• Scope/permission issues
• Rate limiting
• Token refresh failures

api-patterns.md - Common patterns

• Authentication headers
• Pagination
• Batch requests
• Error responses

Service Scopes

The unified token requests all scopes on first login:

| Service | Scopes | |---------|--------| | Gmail | gmail.readonly, gmail.send, gmail.compose, gmail.modify, gmail.labels | | Docs | documents, drive | | Sheets | spreadsheets, drive.readonly | | Calendar | calendar, calendar.events |

Note: User grants all permissions once, then all Google skills work.

File Locations

| File | Location | Purpose | |------|----------|---------| | OAuth credentials | .env (GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET, GOOGLE_PROJECT_ID) | App identity from Google Cloud | | Access token | 01-memory/integrations/google-token.json | User's authenticated token |

How Skills Reference This

Each skill imports the shared auth module:

# In any Google skill's operations script
import sys
from pathlib import Path

# Add google-master to path
NEXUS_ROOT = Path(__file__).resolve().parents[4]  # Adjust based on skill location
sys.path.insert(0, str(NEXUS_ROOT / "00-system/skills/google/google-master/scripts"))

from google_auth import get_credentials, get_service

# Get authenticated service
gmail = get_service('gmail', 'v1')
docs = get_service('docs', 'v1')
sheets = get_service('sheets', 'v4')
calendar = get_service('calendar', 'v3')

Intelligent Error Detection Flow

When a Google skill fails due to missing configuration, the AI should:

Step 1: Run Config Check with JSON Output

python 00-system/skills/google/google-master/scripts/check_google_config.py --json

Step 2: Parse the ai_action Field

| ai_action | What to Do | |-----------|------------| | proceed | Config OK, continue with operation | | install_dependencies | Run: pip install google-auth google-auth-oauthlib google-api-python-client | | need_credentials | Guide user to create OAuth credentials in Google Cloud Console | | need_login | Run: python google_auth.py --login |

Step 3: Help User Fix Issues

If credentials missing:

1. Direct user to: https://console.cloud.google.com/
2. Guide through: APIs & Services > Credentials > Create OAuth Client ID (Desktop app)
3. Copy Client ID and Client Secret, add to .env:

   GOOGLE_CLIENT_ID=your-client-id.apps.googleusercontent.com
   GOOGLE_CLIENT_SECRET=your-client-secret
   GOOGLE_PROJECT_ID=your-project-id
   

4. Run --login to authenticate

Usage Example

User says: "send an email to john@example.com"

What happens:

1. AI loads gmail skill (NOT google-master)
2. gmail SKILL.md says: "Run pre-flight check first"
3. AI executes: python google-master/scripts/google_auth.py --check --service gmail
4. If exit code 0: proceed with gmail_operations.py
5. If exit code 1: run --login automatically
6. If exit code 2: load error-handling.md, guide user through setup

google-master is NEVER loaded directly - it's just a resource library.

Adding New Google Services

To add a new Google service (e.g., Google Drive, Google Tasks):

1. Add scopes to SCOPES dict in google_auth.py
2. Create new skill folder with operations script
3. Import get_service() from google-master
4. Document in this SKILL.md

Version: 1.0 Created: 2025-12-17 Updated: 2025-12-17 Status: Production Ready