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Agents
======

The core idea of agents is to use a language model to choose a sequence of actions to take. In chains, a sequence of actions is hardcoded (in code). In agents, a language model is used as a reasoning engine to determine which actions to take and in which order.

[Quick Start](/v0.1/docs/modules/agents/quick_start/)[​](#quick-start "Direct link to quick-start")
---------------------------------------------------------------------------------------------------

For a quick start to working with agents, please check out [this getting started guide](/v0.1/docs/modules/agents/quick_start/). This covers basics like initializing an agent, creating tools, and adding memory.

[Concepts](/v0.1/docs/modules/agents/concepts/)[​](#concepts "Direct link to concepts")
---------------------------------------------------------------------------------------

There are several key concepts to understand when building agents: Agents, AgentExecutor, Tools, Toolkits. For an in depth explanation, please check out [this conceptual guide](/v0.1/docs/modules/agents/concepts/).

[Agent Types](/v0.1/docs/modules/agents/agent_types/)[​](#agent-types "Direct link to agent-types")
---------------------------------------------------------------------------------------------------

There are many different types of agents to use. For a overview of the different types and when to use them, please check out [this section](/v0.1/docs/modules/agents/agent_types/).

[Tools](/v0.1/docs/modules/agents/tools/)[​](#tools "Direct link to tools")
---------------------------------------------------------------------------

Agents are only as good as the tools they have. For a comprehensive guide on tools, please see [this section](/v0.1/docs/modules/agents/tools/).

How To Guides[​](#how-to-guides "Direct link to How To Guides")
---------------------------------------------------------------

Agents have a lot of related functionality! Check out various guides including:

*   [Building a custom agent](/v0.1/docs/modules/agents/how_to/custom_agent/)
*   [Streaming (of both intermediate steps and tokens)](/v0.1/docs/modules/agents/how_to/streaming/)
*   [Building an agent that returns structured output](/v0.1/docs/modules/agents/how_to/agent_structured/)
*   Lots of functionality around using AgentExecutor, including: [handling parsing errors](/v0.1/docs/modules/agents/how_to/handle_parsing_errors/), [returning intermediate steps](/v0.1/docs/modules/agents/how_to/intermediate_steps/), and [capping the max number of iterations](/v0.1/docs/modules/agents/how_to/max_iterations/).

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