Firestore Operations Manager

Overview

This skill manages Firebase/Firestore operations for both regular web/mobile applications and AI agent-to-agent (A2A) frameworks. It handles:

• Basic Operations: CRUD, queries, batch processing for standard applications
• A2A Framework: Agent-to-agent communication patterns using Firestore as state store
• MCP Integration: Model Context Protocol server communication via Firestore
• Cloud Run Services: Integration patterns for Cloud Run services accessing Firestore
• Security: Proper authentication, validation, and security rules for both humans and agents

Core Capabilities

For Everyone (Basic Firestore)

• Create, read, update, delete documents
• Complex queries with filters and ordering
• Batch operations for efficiency
• Collection management and organization
• Security rules generation and validation
• Data migrations and transformations

For AI Power Users (A2A/MCP)

• Agent session management with Firestore state
• Agent-to-agent messaging and task coordination
• MCP server communication patterns
• Agent memory and context storage
• Cloud Run service integration
• Multi-agent workflow orchestration

When to Use This Skill

This skill activates when users mention:

• Basic operations: "create a firestore document", "query users collection", "batch update documents"
• A2A patterns: "setup agent communication", "A2A task queue", "agent-to-agent messaging"
• MCP integration: "MCP server firestore", "agent memory storage", "session management"
• Cloud Run: "Cloud Run firestore integration", "service account access"
• Security: "firestore security rules", "agent authentication", "service account permissions"

Workflow

Phase 1: Setup and Initialization

For basic users:

1. Check if Firebase Admin SDK is installed
2. Guide through credential setup (service account JSON)
3. Initialize Firestore connection
4. Run connection test
5. Create basic usage examples

For A2A/MCP users:

1. Perform basic setup (above)
2. Install additional dependencies (@google-cloud/firestore)
3. Create A2A collection structure (sessions, memory, tasks, messages, logs)
4. Configure service account whitelisting
5. Setup security rules for agent access
6. Create MCP service wrapper classes

Example setup:

# Basic setup
npm install firebase-admin

# A2A/MCP setup
npm install firebase-admin @google-cloud/firestore dotenv

# Set credentials
export GOOGLE_APPLICATION_CREDENTIALS="./serviceAccountKey.json"

# Run setup command
/firestore-setup

Phase 2: Basic CRUD Operations

For standard database operations:

Create documents:

const { db, admin } = require('./src/firebase');

// Single document
await db.collection('users').add({
  name: 'John Doe',
  email: '[email protected]',
  createdAt: admin.firestore.FieldValue.serverTimestamp()
});

// With custom ID
await db.collection('users').doc('user123').set({
  name: 'Jane Doe',
  email: '[email protected]'
});

Read documents:

// Single document
const doc = await db.collection('users').doc('user123').get();
const userData = doc.data();

// Query
const snapshot = await db.collection('users')
  .where('status', '==', 'active')
  .orderBy('createdAt', 'desc')
  .limit(10)
  .get();

snapshot.forEach(doc => console.log(doc.data()));

Update documents:

// Partial update
await db.collection('users').doc('user123').update({
  status: 'active',
  updatedAt: admin.firestore.FieldValue.serverTimestamp()
});

// Increment counter
await db.collection('stats').doc('views').update({
  count: admin.firestore.FieldValue.increment(1)
});

Delete documents:

// Single delete
await db.collection('users').doc('user123').delete();

// Batch delete
const batch = db.batch();
const docs = await db.collection('temp').limit(500).get();
docs.forEach(doc => batch.delete(doc.ref));
await batch.commit();

Phase 3: A2A Framework Operations

For agent-to-agent communication patterns:

1. Create Agent Session:

const { MCPService } = require('./src/mcp-service');
const mcp = new MCPService('mcp-server@project.iam.gserviceaccount.com');

// Create session for agent workflow
const sessionId = await mcp.createSession({
  task: 'process_user_data',
  priority: 'high',
  metadata: { userId: 'user123' }
});

console.log(`Session created: ${sessionId}`);

2. Store Agent Context:

// Store agent memory/context in Firestore
await mcp.storeContext(sessionId, {
  conversation: [...messages],
  userPreferences: { theme: 'dark' },
  currentStep: 'data_validation'
});

// Retrieve context later
const context = await db
  .collection('agent_memory')
  .doc('mcp-server@project.iam.gserviceaccount.com')
  .collection('contexts')
  .doc(sessionId)
  .get();

3. Agent-to-Agent Messaging:

// Send message from one agent to another
await mcp.sendMessage(
  'agent-engine@project.iam.gserviceaccount.com',
  {
    action: 'analyze_data',
    data: { userId: 'user123', fields: ['name', 'email'] }
  }
);

// Receive messages (in receiving agent)
const messages = await mcp.receiveMessages();
messages.forEach(msg => {
  console.log(`From: ${msg.from}, Payload:`, msg.payload);
});

4. Task Queue Management:

// Create task for another agent
await db.collection('a2a_tasks').add({
  taskType: 'data_processing',
  assignedTo: 'worker-agent@project.iam.gserviceaccount.com',
  status: 'pending',
  priority: 1,
  payload: { userId: 'user123' },
  createdAt: admin.firestore.FieldValue.serverTimestamp()
});

// Agent claims and processes task
const taskQuery = await db.collection('a2a_tasks')
  .where('assignedTo', '==', 'worker-agent@project.iam.gserviceaccount.com')
  .where('status', '==', 'pending')
  .orderBy('priority', 'asc')
  .limit(1)
  .get();

if (!taskQuery.empty) {
  const task = taskQuery.docs[0];
  await task.ref.update({ status: 'in_progress' });
  // Process task...
  await task.ref.update({ status: 'completed' });
}

5. Agent Activity Logging:

// Log agent activities for audit trail
await mcp.logActivity({
  action: 'processed_data',
  userId: 'user123',
  duration: 1500, // ms
  result: 'success'
}, 'info');

Phase 4: Cloud Run Integration

For Cloud Run services accessing Firestore:

Setup Cloud Run service class:

const { CloudRunService } = require('./src/cloudrun-service');
const cloudrun = new CloudRunService();

// In your Cloud Run endpoint
app.post('/api/users/:userId/data', async (req, res) => {
  const { userId } = req.params;

  try {
    // Log request
    await cloudrun.logRequest('/api/users/data', 'POST', userId);

    // Get user data from Firestore
    const userData = await cloudrun.getUserData(userId);

    // Store response
    await cloudrun.storeResponse(req.id, {
      userId,
      data: userData,
      status: 'success'
    });

    res.json({ success: true, data: userData });
  } catch (error) {
    await cloudrun.storeResponse(req.id, {
      userId,
      error: error.message,
      status: 'error'
    });

    res.status(500).json({ error: error.message });
  }
});

Phase 5: Security Rules Management

Generate and deploy security rules for both users and agents:

For basic users:

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /users/{userId} {
      allow read, write: if request.auth != null && request.auth.uid == userId;
    }
  }
}

For A2A/MCP (service accounts):

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    function isServiceAccount() {
      return request.auth.token.email.matches('.*@.*\\.iam\\.gserviceaccount\\.com$');
    }

    function isAuthorizedAgent() {
      return isServiceAccount() && request.auth.token.email in [
        'mcp-server@project-id.iam.gserviceaccount.com',
        'agent-engine@project-id.iam.gserviceaccount.com'
      ];
    }

    // Agent sessions
    match /agent_sessions/{sessionId} {
      allow read, write: if isAuthorizedAgent();
    }

    // Agent memory
    match /agent_memory/{agentId}/{document=**} {
      allow read, write: if isAuthorizedAgent();
    }

    // A2A messages
    match /a2a_messages/{messageId} {
      allow create: if isAuthorizedAgent();
      allow read: if isAuthorizedAgent() &&
                     (resource.data.from == request.auth.token.email ||
                      resource.data.to == request.auth.token.email);
    }
  }
}

Deploy rules:

firebase deploy --only firestore:rules

Advanced Patterns

Pattern 1: Multi-Agent Workflow Orchestration

// Coordinator agent creates workflow
const workflowId = await db.collection('workflows').add({
  name: 'user_data_processing',
  steps: [
    { agent: 'validator@project.iam.gserviceaccount.com', status: 'pending' },
    { agent: 'processor@project.iam.gserviceaccount.com', status: 'pending' },
    { agent: 'notifier@project.iam.gserviceaccount.com', status: 'pending' }
  ],
  createdAt: admin.firestore.FieldValue.serverTimestamp()
});

// Each agent listens for their step
const unsubscribe = db.collection('workflows')
  .doc(workflowId)
  .onSnapshot(async (doc) => {
    const workflow = doc.data();
    const myStep = workflow.steps.find(s => s.agent === myEmail && s.status === 'pending');

    if (myStep) {
      // Process step
      await processStep(myStep);

      // Mark complete and notify next agent
      myStep.status = 'completed';
      await doc.ref.update({ steps: workflow.steps });
    }
  });

Pattern 2: Agent Context Sharing

// Agent 1 stores context
await db.collection('shared_context').doc('task_abc').set({
  sharedBy: 'agent1@project.iam.gserviceaccount.com',
  sharedWith: ['agent2@project.iam.gserviceaccount.com'],
  context: {
    userId: 'user123',
    analysis: { sentiment: 'positive', score: 0.85 }
  },
  expiresAt: new Date(Date.now() + 3600000) // 1 hour
});

// Agent 2 retrieves context
const contextDoc = await db.collection('shared_context').doc('task_abc').get();
if (contextDoc.exists && contextDoc.data().sharedWith.includes(myEmail)) {
  const context = contextDoc.data().context;
  // Use context...
}

Pattern 3: Rate Limiting for Agents

// Check and enforce rate limits
const rateLimitRef = db.collection('rate_limits').doc(agentEmail);
const rateLimitDoc = await rateLimitRef.get();

if (rateLimitDoc.exists) {
  const { count, resetAt } = rateLimitDoc.data();

  if (Date.now() < resetAt && count >= 100) {
    throw new Error('Rate limit exceeded');
  }

  if (Date.now() >= resetAt) {
    // Reset counter
    await rateLimitRef.set({
      count: 1,
      resetAt: Date.now() + 60000 // 1 minute
    });
  } else {
    // Increment counter
    await rateLimitRef.update({
      count: admin.firestore.FieldValue.increment(1)
    });
  }
} else {
  // First request
  await rateLimitRef.set({
    count: 1,
    resetAt: Date.now() + 60000
  });
}

Performance Optimization

For Basic Users:

1. Use batch operations - Write/update 500 docs at once
2. Create indexes - Required for complex queries
3. Paginate results - Use cursor-based pagination
4. Cache frequently read data - Reduce read costs

For A2A/MCP Users:

1. Connection pooling - Reuse Firestore connections
2. Batch agent messages - Combine multiple messages
3. TTL for agent data - Clean up expired sessions automatically
4. Denormalize agent state - Avoid cross-collection queries

Cost Optimization

Firestore costs:

• Document reads: $0.06 per 100k
• Document writes: $0.18 per 100k
• Document deletes: $0.02 per 100k

Reduce costs:

• Use batch writes (1 operation vs 500)
• Cache agent context locally
• Archive old agent logs to Cloud Storage
• Set up billing alerts

Security Best Practices

1. Never allow open access - Always require authentication
2. Whitelist service accounts - Don't allow all service accounts
3. Validate all inputs - Check types, formats, required fields
4. Make logs immutable - Prevent tampering with audit trails
5. Rotate credentials - Change service account keys every 90 days
6. Monitor usage - Set up Firebase console alerts
7. Test rules - Use Firebase Emulator before deploying

Troubleshooting

Issue: Permission Denied

• Check security rules allow the operation
• Verify service account is whitelisted
• Ensure GOOGLE_APPLICATION_CREDENTIALS is set

Issue: A2A Messages Not Delivered

• Verify recipient agent email is correct
• Check message status in Firestore console
• Ensure security rules allow cross-agent messaging

Issue: Rate Limit Errors

• Implement exponential backoff
• Use batch operations
• Increase rate limits in configuration

Issue: Cloud Run Connection Fails

• Verify service account has Firestore permissions
• Check VPC connectivity if using private IP
• Ensure project ID matches in code and credentials

Examples

See

examples/firestore-usage.js

for complete code examples covering:

• Basic CRUD operations
• Complex queries and pagination
• Batch operations
• A2A agent communication
• MCP server integration
• Cloud Run service patterns
• Security rules testing

Resources

• Firestore Documentation
• A2A Protocol Specification
• MCP Documentation
• Cloud Run Integration

Summary

This skill provides comprehensive Firestore operations for:

• Everyone: Standard database CRUD, queries, batch ops, security
• AI Power Users: A2A communication, MCP integration, Cloud Run services, multi-agent workflows

Use

/firestore-setup

to initialize, then leverage the agents and commands for specific operations!