AI agent architecture defines how agents receive work, share context, call tools, communicate, and return a result. The right pattern depends less on the number of agents than on the shape of the work: which steps depend on one another, which can run in parallel, who owns shared state, and where review must happen.

For most production systems, the useful patterns are sequential pipelines, routers, supervisors with subagents, handoffs, peer-to-peer teams, and hybrids. Start with the simplest pattern that expresses the real dependencies. Add parallelism only where tasks are independent, and add coordination only where it reduces uncertainty enough to justify more calls and more failure modes.

AI Agent Architecture at a Glance

PatternControl modelBest forMain risk
Sequential pipelineFixed ordered stepsPredictable dependent workSlow end-to-end execution
RouterOne decision selects a specialistClear request categoriesMisrouting and weak fallback behavior
Supervisor and subagentsCentral planner delegates tasksParallel specialist workBottleneck or stale coordinator context
HandoffActive agent transfers controlConversations and changing responsibilityLost context at boundaries
Peer-to-peerAgents communicate directlySmall collaborative teamsMessage growth and unclear ownership
HybridDifferent patterns by stageComplex production workflowsOperational complexity

The table is a starting point, not a maturity ladder. A sequential workflow can be more reliable than a swarm. A router can outperform a supervisor when the only real decision is which specialist should handle the request.

1. Sequential Pipelines for Dependent Work

A sequential pipeline runs one agent or step after another. The output of one stage becomes the input to the next: plan, implement, test, and review.

This pattern fits tasks with real dependencies. A reviewer cannot evaluate code that has not been written, and an implementation agent should not target an interface that a planning step has not defined. The ordered structure makes state transitions visible and limits concurrent writes.

The tradeoff is latency. Independent steps wait even when they could run safely in parallel. Pipelines also need explicit failure handling: a failed step should stop, retry, or route to a human rather than silently passing incomplete output downstream.

Use a sequential pipeline when:

  • each step consumes the previous step’s result;
  • reproducibility matters more than minimum latency;
  • the workflow modifies one shared resource;
  • review gates must occur in a fixed order.

2. Routers for Clear Categories

A router classifies the request and sends it to one specialist. A coding request might go to an implementation agent, a documentation request to a writer, and a release failure to an operations agent.

Routing is efficient because only the selected specialist runs. It also keeps prompts and tools scoped to the task. The architecture fails when categories overlap or the router lacks a safe fallback. A low-confidence request should go to a generalist or a human instead of being forced into the nearest label.

Use a router when:

  • requests fall into stable, distinguishable categories;
  • one specialist usually owns the complete task;
  • tool access differs by category;
  • cost matters more than collaborative deliberation.

3. Supervisors and Subagents for Parallel Specialists

In a supervisor pattern, one agent decomposes the goal, delegates bounded tasks, collects results, and decides what happens next. Subagents usually do not need the whole conversation; each receives the context and tools required for its assignment.

This pattern is useful when research, implementation, testing, or analysis can proceed independently. It creates one place for prioritization and synthesis, which makes the workflow easier to inspect than an unrestricted mesh.

The supervisor can become a bottleneck. It may hold stale information while workers change the environment, or it may spend more tokens restating context than the task saves through parallelism. Keep delegation contracts small: objective, inputs, writable resources, completion criteria, and escalation path.

Use a supervisor when:

  • the goal can be decomposed into independent tasks;
  • one component should own the final answer;
  • workers need different tools or expertise;
  • central review is a feature, not a throughput constraint.

4. Handoffs for Changing Responsibility

A handoff transfers active control from one agent to another. Unlike a supervisor, the first agent may not remain in the loop. Customer-support systems use this pattern when a triage agent transfers a conversation to billing or technical support.

For coding work, handoffs are useful when the task moves between distinct phases or owners. They require a durable handoff record: what was requested, what was observed, which files or resources changed, what remains uncertain, and what the next agent may do.

The failure mode is context loss. Forwarding an entire transcript creates noise; forwarding only a summary can omit the assumption that later causes a bug. Treat the handoff as an explicit artifact rather than an informal message.

5. Peer-to-Peer Teams for Rich Collaboration

Peer-to-peer agents communicate directly without routing every message through one coordinator. This can reduce a central bottleneck and let specialists resolve local questions quickly.

The costs rise fast. More possible edges create more messages, more model calls, and more opportunities for duplicated or contradictory work. Direct communication also makes ownership harder to see unless the system records claims and task state separately.

The LLM traffic management guide shows why topology is also an infrastructure decision. Star and full-mesh graphs can create synchronized bursts and higher concurrency even when the user sees one task.

Use peer-to-peer coordination when:

  • the team is small;
  • specialists genuinely need iterative exchange;
  • communication rules are explicit;
  • task ownership and shared-state protection exist outside the chat.

6. Hybrid Architectures for Production Workflows

Most useful systems combine patterns. A router selects a workflow, a supervisor launches independent research tasks, a sequential pipeline applies changes, and a reviewer accepts or rejects the result.

Hybrid does not mean connecting every pattern. It means choosing a control model for each stage. Draw the workflow as states and transitions before assigning agents. If the diagram cannot explain who owns a decision or resource, adding another agent will not fix it.

A practical coding workflow might look like this:

  1. A router classifies the request as a bug, feature, documentation task, or investigation.
  2. A planner identifies dependencies and assigns resource ownership.
  3. Independent agents work in isolated branches or worktrees.
  4. Tests run after each change and again after integration.
  5. A reviewer inspects the diff, tool history, and test evidence.
  6. A human accepts, revises, or rejects the result.

Reliability Is a Separate Layer

Architecture decides how work flows. Reliability controls decide what is allowed to happen while it flows.

At minimum, a multi-agent system needs:

  • Task state: a durable record of queued, running, blocked, review, and completed work.
  • Resource ownership: an explicit claim on files, records, tools, or environments that agents may modify.
  • Version checks: a way to detect that shared state changed after an agent read it.
  • Isolation: separate branches, worktrees, sandboxes, or transactions for risky changes.
  • Budgets: limits for calls, tokens, time, retries, and concurrent workers.
  • Observability: readable tool events, messages, errors, and decisions.
  • Review gates: tests and human acceptance before high-impact changes become final.

These controls address failures that prompt design alone cannot solve. The guide to concurrency control for multi-agent AI explains stale reads, lost updates, versions, locks, and branch isolation in detail.

How to Choose the Right Pattern

Use five questions to choose an architecture:

Are the steps dependent?

Use a sequence for dependent steps. Parallel execution is appropriate only when tasks can complete against stable inputs.

Does one component need to synthesize the result?

Use a supervisor when one agent must reconcile evidence or produce the final artifact. Use a router when only one specialist needs to run.

Can agents modify the same resource?

If yes, add ownership, version checks, or isolation before adding parallelism. Coordination messages do not prevent write conflicts.

How expensive is communication?

Each handoff or peer message can create another model call and a larger context. Measure task duration and peak concurrency, not just total token count.

Where must a human decide?

Put review before irreversible actions, external publication, payment, deployment, or merging into shared code. The agent graph should make that boundary obvious.

An Architecture Review Checklist

Before implementation, verify that the design answers:

  1. What starts and ends the workflow?
  2. Which steps are sequential, and which are truly independent?
  3. Who owns each task and writable resource?
  4. What context crosses each routing or handoff boundary?
  5. How are stale reads and conflicting writes detected?
  6. What limits calls, retries, runtime, and concurrent workers?
  7. Which events are recorded for debugging and review?
  8. What evidence must exist before the result is accepted?

If those answers are clear, the architecture is ready for a small measured trial. If they are not, a larger agent team will usually amplify the ambiguity.

How Dorchestrator Applies These Patterns

Dorchestrator is a local-first workspace for running coding-agent workflows with visible task state, agent communication, isolated workspaces, tool timelines, and human review. It supports graph-based teams without assuming that every task needs a swarm.

The practical goal is controlled orchestration: use Kanban for durable task state, Swarm for connected multi-agent work, Mux for repeatable terminal layouts, and explicit review before accepting a result. See the coding-agent orchestration workspace for the product model.

Sources and Further Reading