Workflow Agents¶
This section introduces "workflow agents" - specialized agents that control the execution flow of its sub-agents.
Workflow agents are specialized components in ADK designed purely for orchestrating the execution flow of sub-agents. Their primary role is to manage how and when other agents run, defining the control flow of a process.
Unlike LLM Agents, which use Large Language Models for dynamic reasoning and decision-making, Workflow Agents operate based on predefined logic. They determine the execution sequence according to their type (e.g., sequential, parallel, loop) without consulting an LLM for the orchestration itself. This results in deterministic and predictable execution patterns.
ADK provides three core workflow agent types, each implementing a distinct execution pattern:
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Sequential Agents
Executes sub-agents one after another, in sequence.
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Loop Agents
Repeatedly executes its sub-agents until a specific termination condition is met.
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Parallel Agents
Executes multiple sub-agents in parallel.
Why Use Workflow Agents?¶
Workflow agents are essential when you need explicit control over how a series of tasks or agents are executed. They provide:
- Predictability: The flow of execution is guaranteed based on the agent type and configuration.
- Reliability: Ensures tasks run in the required order or pattern consistently.
- Structure: Allows you to build complex processes by composing agents within clear control structures.
While the workflow agent manages the control flow deterministically, the sub-agents it orchestrates can themselves be any type of agent, including intelligent LlmAgent instances. This allows you to combine structured process control with flexible, LLM-powered task execution.