Core agent orchestration patterns
Orchestration patterns determine how agents interact. Choosing the right pattern is the most consequential architectural decision in a multi-agent system, because changing it after deployment is expensive.
Sequential pattern
The sequential pattern routes tasks through agents in a fixed order, where each agent's output becomes the next agent's input. This is the simplest and most predictable pattern.
When to use:
- Workflows with clear, linear dependencies (document review, multi-stage approval, and content generation pipelines)
When to avoid:
- Tasks that require parallel processing
- Workflows where the step order may vary
- Time-sensitive operations where sequential processing creates bottlenecks
Example: A law firm's contract review pipeline where Agent 1 extracts key terms, Agent 2 checks compliance against regulatory requirements, and Agent 3 generates a summary with flagged risks
Pitfall: A low-quality or incorrect output from one agent propagates silently through the rest of the chain. Because each agent trusts the previous agent's output, errors compound rather than surface.
Mitigation: Build output validation checks between steps, set confidence thresholds that trigger human review before the next agent proceeds, and log each agent's output independently so failures can be traced to their source.
Concurrent pattern
The concurrent pattern executes multiple agents in parallel on independent subtasks, then aggregates their outputs. This maximizes throughput when tasks do not depend on each other.
When to use:
- Independent analyses that can run simultaneously (multi-source market research, parallel data validation, and concurrent risk assessments)
When to avoid:
- When agents need each other's outputs to operate
- When the aggregation logic is more complex than the parallel work itself
Example: A stock analysis system where a financial analysis agent processes company filings, a sentiment agent monitors news and social signals, and a technical analysis agent evaluates price and volume indicators; results are aggregated into a single recommendation, with conflict resolution logic handling contradictions.
Pitfall: Concurrent agents may produce conflicting conclusions. Mitigation requires defined reconciliation rules (majority voting, confidence scoring, or escalation to human review).
Mitigation:
- Define a reconciliation method before deployment (voting, confidence scoring, or rule-based override).
- Set a clear escalation path for unresolvable conflicts.
- Log all conflicting outputs for audit and model improvement.
Group chat pattern
The group chat pattern enables multiple agents to contribute to a shared thread, iterating collaboratively toward a solution. A maker-checker variant has one agent propose outputs while another validates them.
When to use: Complex problems that require multiple perspectives (product design review, policy analysis, and cross-functional planning)
When to avoid: Simple tasks where the overhead of multi-agent discussion exceeds the value, or time-sensitive workflows
Example: A municipal planning process where an urban planning agent proposes infrastructure changes, a budget analysis agent evaluates costs, and a regulatory compliance agent flags permit requirements; the threaded discussion format provides a natural audit trail.
Pitfall: Agents can loop indefinitely without converging on a resolution, particularly when two agents hold contradictory positions and no arbitration rule is defined.
Mitigation: Set a maximum number of discussion turns before a human reviewer or supervisor agent is brought in, define a default resolution rule (such as deferring to the agent with the highest confidence score), and log the full thread for audit.
Handoff pattern
The handoff pattern dynamically delegates tasks between agents based on the current context. Unlike sequential patterns, the routing is determined at runtime based on the task's characteristics.
When to use: Customer service workflows where the initial request type is unknown (triage agent routes to billing, technical support, or account management based on intent classification)
When to avoid: When routing logic is simple enough for static rules
Example: A telecom CRM system where a triage agent classifies incoming requests and hands them to specialized agents for billing disputes, technical troubleshooting, or plan upgrades; each specialist agent has access to different data sources and different authorization levels.
Pitfalls: It entails infinite routing loops (Agent A hands to Agent B, which hands back to Agent A) and misrouted requests.
Mitigation: Include guardrails like maximum handoff limits, timeout thresholds, and automatic escalation to human review after a defined number of transfers.
Hierarchical and federated variants
Hierarchical and federated patterns represent two approaches to managing agent coordination at the organizational level. Both suit enterprise environments where scale, privacy, or regulatory complexity make simpler patterns insufficient.
Click on the image above to zoom into full PDF