← Back|AI-AGENTS›Section 1/16

0 of 16 completed

Agent communication basics

Intermediate⏱ 10 min read📅 Updated: 2026-02-17

💬 Introduction – Agents Need to Talk!

Single agent alone work pannalaam. But multiple agents collaborate pannanum na, communication essential! 🤝

Think of it like a team project:

👨‍💼 Manager assigns tasks
👩‍💻 Developer builds features
🧪 Tester finds bugs
📝 Writer creates docs

They all need to communicate to succeed! Same for AI agents! 🤖💬🤖

Agent Communication = How agents share information, coordinate tasks, and collaborate to achieve goals.

This article covers:

📨 Message passing fundamentals
🔄 Communication patterns
📋 Protocols and standards
🤝 Coordination strategies
⚠️ Common pitfalls

📨 Message Passing Fundamentals

Basic unit of agent communication = Message

Message Structure:

code

{
  "from": "researcher_agent",
  "to": "writer_agent",
  "type": "task_result",
  "content": "Found 5 key trends in AI...",
  "metadata": {
    "timestamp": "2026-02-17T10:30:00",
    "priority": "high",
    "task_id": "research-001"
  }
}

Message Types:

Type	Purpose	Example
Task Assignment	Delegate work	"Research this topic"
Task Result	Return findings	"Here are the results"
Status Update	Progress report	"50% complete"
Query	Ask for info	"What's the deadline?"
Response	Answer query	"Deadline is Friday"
Error	Report problem	"API call failed"
Coordination	Synchronize	"Ready for next step"

Every message should have: sender, receiver, type, content, timestamp! 📨

🔄 Communication Patterns

Pattern 1: Request-Response 🔄

code

Agent A: "Search for AI trends" →
Agent B: ← "Here are 5 trends: ..."

Simple, synchronous. One asks, one answers.

Pattern 2: Publish-Subscribe 📢

code

Agent A publishes: "New data available"
Agent B (subscribed): Receives notification
Agent C (subscribed): Receives notification
Agent D (not subscribed): Doesn't know

One-to-many communication. Great for events.

Pattern 3: Broadcast 📡

code

Manager: "Meeting at 3 PM" → ALL agents

One agent sends to all. For important announcements.

Pattern 4: Pipeline (Chain) ⛓️

code

Agent A → output → Agent B → output → Agent C

Sequential processing. Each agent adds value.

Pattern 5: Blackboard 📋

code

Shared Space (Blackboard):
- Agent A writes research findings
- Agent B reads findings, writes analysis
- Agent C reads analysis, writes report

Indirect communication via shared space.

Pattern	Best For	Coupling
Request-Response	Direct queries	Tight
Pub-Sub	Event notifications	Loose
Broadcast	Team announcements	Loose
Pipeline	Sequential workflows	Medium
Blackboard	Collaborative work	Loose

🏗️ Agent Communication Architecture

🏗️ Architecture Diagram

```
┌─────────────────────────────────────────────┐
│            COMMUNICATION LAYER              │
│                                             │
│  ┌──────────────────────────────────────┐   │
│  │       📬 MESSAGE BUS / BROKER        │   │
│  │  Route │ Queue │ Prioritize │ Log    │   │
│  └──────┬────────────┬──────────┬───────┘   │
│         │            │          │            │
│   ┌─────▼─────┐ ┌───▼────┐ ┌──▼──────┐    │
│   │ 👨‍💼 Manager│ │🔍Research│ │✏️ Writer │    │
│   │  Agent    │ │  Agent  │ │  Agent  │    │
│   └───────────┘ └────────┘ └─────────┘    │
│         │            │          │            │
│   ┌─────▼────────────▼──────────▼───────┐   │
│   │       📋 SHARED STATE / MEMORY       │   │
│   │  Task Board │ Results │ Context      │   │
│   └─────────────────────────────────────┘   │
│                                             │
│   ┌─────────────────────────────────────┐   │
│   │       📊 MONITOR & LOGGING          │   │
│   │  Message count │ Latency │ Errors   │   │
│   └─────────────────────────────────────┘   │
└─────────────────────────────────────────────┘
```

🤝 Coordination Strategies

Multiple agents coordinate panna different strategies irukku:

1. Centralized Coordination 👑

One manager agent controls everything
Sub-agents report to manager
Manager decides next steps

Pros	Cons
Clear control	Single point of failure
Easy to track	Manager bottleneck
Predictable	Less flexible

2. Decentralized Coordination 🌐

No single controller
Agents negotiate with each other
Consensus-based decisions

Pros	Cons
No bottleneck	Harder to track
Fault tolerant	Potential conflicts
Scalable	More complex

3. Hybrid Coordination 🔄

Manager for high-level planning
Peer-to-peer for execution details
Best of both worlds!

Recommendation: Start with centralized (simpler), move to hybrid for production! 🎯

🎬 Communication in Action – Customer Support

✅ Example

Multi-Agent Customer Support System:

code

[Customer]: "My order #456 hasn't arrived and I was charged twice"

[Router Agent] → Classifies: ORDER_ISSUE + BILLING_ISSUE
  → Sends to Order Agent + Billing Agent (parallel)

[Order Agent]:
  → Queries order DB
  → Message to Router: "Order #456 shipped, delayed due to weather.
     ETA: Feb 19. Tracking: TRK789"

[Billing Agent]:
  → Queries payment DB
  → Message to Router: "Double charge confirmed. 
     Refund of ₹1,500 initiated. Ref: REF-321"

[Router Agent] → Combines responses
  → Sends to Response Agent

[Response Agent] → Crafts unified reply:
"Hi! I checked your order #456 – it's on the way, delayed 
by weather (ETA Feb 19, tracking: TRK789). I also found the 
double charge and initiated a ₹1,500 refund (Ref: REF-321). 
Should arrive in 3-5 business days. Anything else? 😊"

4 agents, 1 seamless response! ✨

📋 Communication Protocols

Agents communicate panna standardized protocols help pannum:

1. Natural Language Protocol 💬

Agents chat in plain text
Flexible but ambiguous
Best for: Creative collaboration

2. Structured Message Protocol 📊

json

{
  "action": "SEARCH",
  "params": {"query": "AI trends", "limit": 5},
  "response_format": "JSON"
}

Clear, unambiguous
Best for: Tool-using agents

3. Function Calling Protocol 🔧

Agent A calls Agent B as a function
Typed inputs/outputs
Best for: Tight integration

4. Event-Driven Protocol 📡

code

Event: "new_data_available"
Payload: {"source": "api", "records": 100}
Subscribers: [analyst_agent, report_agent]

Loose coupling
Best for: Scalable systems

Protocol	Reliability	Flexibility	Complexity
Natural Language	Low	High	Low
Structured Message	High	Medium	Medium
Function Calling	Very High	Low	Medium
Event-Driven	High	High	High

⚠️ Communication Challenges

Challenge 1: Context Loss 📉

Agent A knows something, but forgets to tell Agent B

*Fix:* Explicit context passing in every message

Challenge 2: Message Ordering 🔢

Messages arrive out of order

*Fix:* Timestamps + sequence numbers + message queue

Challenge 3: Infinite Loops 🔄

Agent A asks B, B asks A, A asks B...

*Fix:* Max message count per task, loop detection

Challenge 4: Conflicting Instructions ⚔️

Agent A says "use formal tone", Agent B says "use casual"

*Fix:* Priority hierarchy, manager as tiebreaker

Challenge 5: Information Overload 🌊

Too many messages overwhelm agent's context window

*Fix:* Message summarization, relevance filtering

Challenge 6: Latency ⏱️

Each agent interaction adds latency

*Fix:* Parallel communication, async processing

Prevention checklist:

✅ Clear message format defined
✅ Max iterations per conversation set
✅ Context explicitly passed
✅ Error handling for communication failures
✅ Monitoring for unusual patterns

🧪 Try It – Simulate Agent Communication

📋 Copy-Paste Prompt

```
Simulate a 3-agent system handling this task:
"Analyze last month's sales data and create a presentation"

AGENTS:
1. DATA_AGENT: Accesses databases, runs queries
2. ANALYST_AGENT: Interprets data, finds insights
3. PRESENTER_AGENT: Creates slides and visuals

RULES:
- Show each message between agents
- Format: [SENDER → RECEIVER]: "message"
- Show at least 8 messages
- Include one error scenario and recovery

START:
[MANAGER → DATA_AGENT]: "Fetch last month's sales data 
from the database"

Continue the conversation...
```

Great way to understand multi-agent communication flow! 🔄

🛠️ Tools for Agent Communication

Tool/Framework	Communication Style	Best For
CrewAI	Role-based delegation	Simple teams
AutoGen	Conversational	Chat-based collaboration
LangGraph	State-based routing	Complex workflows
Swarm	Lightweight handoffs	Simple agent switching
RabbitMQ	Message queue	Production messaging
Redis Pub/Sub	Event-driven	Real-time events
gRPC	Function calls	High-performance

For beginners: CrewAI or AutoGen – built-in agent communication! 🚀

For production: LangGraph + Redis/RabbitMQ – scalable and reliable! 🏢

💡 Communication Best Practices

💡 Tip

1. Keep messages concise – Essential info only, no filler

2. Use structured formats – JSON > free text for reliability

3. Include context – Don't assume other agent knows everything

4. Set timeouts – Don't wait forever for a response

5. Log everything – Debug communication issues easily

6. Idempotent messages – Same message twice = same result

7. Acknowledge receipt – Confirm message received before processing

8. Version your protocols – Evolve without breaking existing agents

🔒 Security in Agent Communication

Agent communication secure pannanum:

Threat	Risk	Mitigation
Message tampering	Altered instructions	Message signing
Impersonation	Fake agent sends messages	Authentication tokens
Eavesdropping	Sensitive data intercepted	Encryption (TLS)
Injection	Malicious prompts injected	Input validation
DoS	Flood of messages	Rate limiting

Minimum security:

✅ Authenticate every agent (API keys/tokens)
✅ Validate all incoming messages
✅ Encrypt sensitive data in transit
✅ Rate limit message frequency
✅ Audit log all communications

📝 Summary

Key Takeaways:

✅ Agent communication = Messages with sender, receiver, type, content

✅ 5 Patterns: Request-Response, Pub-Sub, Broadcast, Pipeline, Blackboard

✅ Coordination: Centralized (simple) → Hybrid (production)

✅ Protocols: Natural Language, Structured, Function Call, Event-Driven

✅ Challenges: Context loss, ordering, loops, conflicts, overload

✅ Security: Authentication, encryption, validation, rate limiting

✅ Tools: CrewAI/AutoGen (simple), LangGraph+Redis (production)

Next article la APIs inside Agents paapom – agents external services epdi use pannும்! 🔌

🏁 🎮 Mini Challenge

Challenge: Design Agent Communication Protocol

Multi-agent system-ku communication protocol design panni structure define:

Scenario: 3-agent blog writing team (Researcher, Writer, Editor)

Step 1: Define Message Structure (4 mins)

Standard JSON message template create:

json

{
  "from": "researcher_agent",
  "to": "writer_agent",
  "type": "task_result",
  "task_id": "blog_001",
  "content": "Found 5 key trends...",
  "priority": "high",
  "timestamp": "2026-02-23T10:30:00",
  "requires_ack": true
}

Step 2: Define Communication Patterns (4 mins)

Researcher → Writer → Editor → User

Pattern: Pipeline (sequential)

Researcher finishes → sends to Writer
Writer finishes → sends to Editor
Editor finishes → sends to User

Step 3: Error Handling Protocol (3 mins)

Message timeout? → Retry 3 times
Agent not responding? → Escalate to human
Invalid message format? → Request reformat
Low quality output? → Request improvement

Step 4: Implement Message Flow (3 mins)

Pseudo-code:

code

Researcher executes research
├─ Creates message {"content": research_results}
├─ Sends to Writer queue
└─ Waits for ack

Writer receives message
├─ Processes research_results
├─ Creates message {"content": draft}
├─ Sends to Editor queue
└─ Waits for feedback

Editor receives message
├─ Reviews draft
├─ Sends final approval message
└─ User gets result

Communication protocol complete! 📨

💼 Interview Questions

Q1: Agents epdi effectively communicate pannum?

A: Structured messages: sender, receiver, type, content, metadata. Ambiguity avoid. Context loss prevent. Protocol define. Example: {"from": "Agent A", "to": "Agent B", "type": "task", "content": {...}}

Q2: Agent communication patterns – when which use?

Request-Response: Simple, synchronous, 1-1 communication
Pub-Sub: Events, broadcasting, decoupling
Pipeline: Sequential workflow (blog writing)
Blackboard: Shared state (collaborative)
Hybrid: Complex systems

Choose based on workflow type!

Q3: Agent communication la biggest challenge?

A: Context loss! Agent A-ku therinja details Agent B-ku clear auto come through? Illa! Explicitly pass pannanum. Standardized message format + comprehensive context = critical!

Q4: 10 agents communicate pannaa enna aagum?

A: Communication explosion! 10 agents = potential 45 message paths! Complexity, latency, cost explode. Solution: Hierarchical communication (central coordinator) or pub-sub (event-driven) use!

Q5: Agent communication security?

Authentication: Verify sender identity
Encryption: Protect message content
Validation: Verify message structure
Rate limiting: Prevent spam
Audit logs: Track all communication

Production systems: All 5 implement pannum must! 🔒

❓ Frequently Asked Questions

❓ Agents epdi oruthu oruthu kitta pesும்?

Message passing, shared memory, event systems, or direct function calls. Most common method is structured message passing – JSON messages with role, content, and metadata.

❓ Agent communication la biggest challenge enna?

Context loss between agents. Agent A ku therinja info Agent B ku theriyaadhu unless explicitly passed. Shared context management critical.

❓ Human language la agents communicate pannuma?

Yes and No. Inter-agent messages can be natural language (LLM-to-LLM) or structured data (JSON/protocol buffers). Structured is more reliable, natural language is more flexible.

❓ How many agents can communicate simultaneously?

Technically unlimited, but practically 3-10 agents optimal. More agents = more communication overhead = slower and more expensive.

🧠Knowledge Check

Quiz 1 of 1

Test your knowledge:

0 of 1 answered

← Previous ByteAI task automation Next Byte →Using APIs inside agents

Courses

Learning Paths

Exam Prep

Agent communication basics

💬 Introduction – Agents Need to Talk!

📨 Message Passing Fundamentals

🔄 Communication Patterns

🏗️ Agent Communication Architecture

🤝 Coordination Strategies

🎬 Communication in Action – Customer Support

📋 Communication Protocols

⚠️ Communication Challenges

🧪 Try It – Simulate Agent Communication

🛠️ Tools for Agent Communication

💡 Communication Best Practices

🔒 Security in Agent Communication

📝 Summary

🏁 🎮 Mini Challenge

💼 Interview Questions

❓ Frequently Asked Questions