Implementing ORCH Profile

The ORCH profile extends CORE with Layer 6 (Orchestration) for multi-agent coordination.

Overview

ORCH profile = CORE profile (L1-L5) + Layer 6 (Orchestration)

This enables:

Multi-agent routing and coordination
Load balancing across agent instances
Circuit breakers for failure handling
Graceful degradation

Requirements

Prerequisites

✅ CORE profile compliance (L1-L5)
✅ Multiple agent instances
✅ Service discovery mechanism
✅ Distributed tracing support

L6 Orchestration Checklist

Implementation

Orchestrator Setup

from aral import Orchestrator, CircuitBreaker, LoadBalancer

orchestrator = Orchestrator(
    orchestrator_id="orch-1",
    port=8081
)

# Configure circuit breaker
circuit_breaker = CircuitBreaker(
    failure_threshold=5,
    success_threshold=3,
    timeout_ms=60000,
    half_open_requests=1
)
orchestrator.set_circuit_breaker(circuit_breaker)

# Configure load balancer
load_balancer = LoadBalancer(
    strategy="health_based",
    minimum_health_score=0.7
)
orchestrator.set_load_balancer(load_balancer)

# Start orchestrator
orchestrator.start()

Agent Registration

# Agent registers with orchestrator
agent_info = {
    "id": "agent-1",
    "endpoint": "http://agent1:8080",
    "health_endpoint": "http://agent1:8080/health",
    "capabilities": ["web_search", "calculate"],
    "version": "1.0.0"
}

orchestrator.register_agent(agent_info)

Request Routing

@orchestrator.route("/invoke")
def route_request(request):
    # Extract requirements
    required_capability = request.json.get("capability")
    trace_id = request.headers.get("X-Trace-Id")

    # Find suitable agent
    agent = orchestrator.select_agent(
        capability=required_capability,
        trace_id=trace_id
    )

    if not agent:
        return {
            "error": "no_agent_available",
            "message": "No agent with required capability found"
        }, 503

    # Check persona constraints
    if not orchestrator.validate_persona(agent, request.json):
        return {
            "error": "persona_violation",
            "message": "Request violates agent persona constraints"
        }, 403

    # Forward request
    return orchestrator.forward_request(agent, request, trace_id)

Circuit Breaker Implementation

class CircuitBreaker:
    def __init__(self, failure_threshold, success_threshold, timeout_ms):
        self.failure_threshold = failure_threshold
        self.success_threshold = success_threshold
        self.timeout_ms = timeout_ms
        self.state = "closed"
        self.failures = {}
        self.successes = {}

    def call(self, agent_id, func):
        """Execute function with circuit breaker"""
        if self.state == "open":
            if self._should_try_half_open(agent_id):
                self.state = "half_open"
            else:
                raise CircuitBreakerOpen(f"Circuit open for {agent_id}")

        try:
            result = func()
            self._record_success(agent_id)
            return result
        except Exception as e:
            self._record_failure(agent_id)
            raise

    def _record_failure(self, agent_id):
        """Record failure and potentially open circuit"""
        self.failures[agent_id] = self.failures.get(agent_id, 0) + 1

        if self.failures[agent_id] >= self.failure_threshold:
            self.state = "open"
            self.opened_at = time.time()

    def _record_success(self, agent_id):
        """Record success and potentially close circuit"""
        self.successes[agent_id] = self.successes.get(agent_id, 0) + 1

        if self.state == "half_open":
            if self.successes[agent_id] >= self.success_threshold:
                self.state = "closed"
                self.failures[agent_id] = 0

Load Balancing

class LoadBalancer:
    def __init__(self, strategy="health_based"):
        self.strategy = strategy

    def select_agent(self, agents, capability=None):
        """Select best agent based on strategy"""
        # Filter by capability
        if capability:
            agents = [a for a in agents if capability in a.capabilities]

        if not agents:
            return None

        if self.strategy == "round_robin":
            return self._round_robin(agents)
        elif self.strategy == "least_connections":
            return self._least_connections(agents)
        elif self.strategy == "health_based":
            return self._health_based(agents)
        else:
            return agents[0]

    def _health_based(self, agents):
        """Select agent with best health score"""
        healthy_agents = [a for a in agents if a.health_score > 0.7]
        if not healthy_agents:
            return None
        return max(healthy_agents, key=lambda a: a.health_score)

Persona Constraint Enforcement

def validate_persona(orchestrator, agent, request):
    """Validate request against agent persona"""
    capability = request["capability"]
    persona = agent.persona

    # Check allowed capabilities
    if capability in persona.constraints["denied_capabilities"]:
        orchestrator.log_violation(agent.id, capability, "denied")
        return False

    allowed = persona.constraints["allowed_capabilities"]
    if "*" not in allowed and capability not in allowed:
        orchestrator.log_violation(agent.id, capability, "not_allowed")
        return False

    return True

Trace Propagation

def forward_request(orchestrator, agent, request, trace_id):
    """Forward request with trace context"""
    headers = {
        "X-Trace-Id": trace_id,
        "X-Parent-Span-Id": request.span_id,
        "X-Span-Id": str(uuid.uuid4())
    }

    response = requests.post(
        f"{agent.endpoint}/invoke",
        json=request.json,
        headers=headers,
        timeout=30
    )

    return response.json()

Health Monitoring

import asyncio

async def monitor_agent_health(orchestrator):
    """Continuously monitor agent health"""
    while True:
        for agent in orchestrator.agents:
            try:
                response = requests.get(
                    agent.health_endpoint,
                    timeout=5
                )

                if response.status_code == 200:
                    health_data = response.json()
                    agent.health_score = 1.0
                    agent.last_heartbeat = time.time()
                else:
                    agent.health_score *= 0.8
            except Exception:
                agent.health_score *= 0.5

        await asyncio.sleep(10)

Testing ORCH Profile

# Start multiple agents
python agent.py --port 8080 &
python agent.py --port 8081 &
python agent.py --port 8082 &

# Start orchestrator
python orchestrator.py --port 8090 &

# Run ORCH tests
aral-test --orchestrator-url http://localhost:8090 --profile ORCH

Example: Multi-Agent Request

# Client sends request to orchestrator
response = requests.post(
    "http://localhost:8090/invoke",
    json={
        "capability": "web_search",
        "parameters": {
            "query": "ARAL specification"
        }
    },
    headers={
        "X-Trace-Id": "trace-123"
    }
)

# Orchestrator:
# 1. Finds agents with "web_search" capability
# 2. Selects healthiest agent
# 3. Checks persona constraints
# 4. Forwards request with trace context
# 5. Returns response to client

Graceful Degradation

def handle_agent_failure(orchestrator, primary_agent, request):
    """Handle failure with fallback"""
    try:
        return orchestrator.call_agent(primary_agent, request)
    except AgentUnavailable:
        # Try fallback
        fallback = orchestrator.find_fallback(primary_agent)
        if fallback:
            return orchestrator.call_agent(fallback, request, degraded=True)
        else:
            return {
                "error": "all_agents_unavailable",
                "degraded_mode": True
            }

Best Practices

Monitor Health Continuously: Check agent health every 10 seconds
Set Appropriate Thresholds: Circuit breaker should trip at 5 failures
Use Trace Context: Always propagate trace IDs for debugging
Implement Timeouts: 30 seconds for normal requests
Load Balance Fairly: Consider health, load, and capabilities
Log Everything: Routing decisions, failures, violations
Test Failure Scenarios: Verify circuit breaker works
Plan for Degradation: Define fallback strategies

Next Steps

INTEROP Profile

Add protocol layer for external communication

Multi-Agent Example

See orchestration in action

Specification

Read L6 requirements