> ## Documentation Index
> Fetch the complete documentation index at: https://relevanceai.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Tools

> The actions your agents use to get things done — from API calls to LLM prompts to custom code.

## What are Tools?

Tools are the actions your agents can take. They're step-by-step automations you build in a no-code builder — things like calling an API, running an LLM prompt, sending an email, searching a database, or executing custom code.

You can give tools to your agents so they know how to complete tasks, share them as standalone forms, or run them in bulk across a knowledge table.

## What are the benefits of Tools?

<CardGroup cols={2}>
  <Card title="Extend what agents can do" icon="puzzle-piece">
    Without tools, agents can only talk. With tools, they can take real actions — update your CRM, send emails, search the web, and more.
  </Card>

  <Card title="No-code builder" icon="wand-magic-sparkles">
    Build tools visually by chaining steps together. No engineering required.
  </Card>

  <Card title="Reusable across agents" icon="clone">
    Build a tool once and give it to any agent. Share it with your team or publish it to the Marketplace.
  </Card>

  <Card title="Full flexibility" icon="code">
    Use pre-built integrations, call any API, or write custom Python. Whatever your workflow needs.
  </Card>
</CardGroup>

## How Tools Work

Every tool follows the same pattern: **inputs → steps → outputs**.

* **Inputs** — the data the tool receives. Text, numbers, files, or data passed from an agent or another tool.
* **Steps** — the actions the tool performs in sequence. Each step can use the output of previous steps. Steps include LLM prompts, API calls, integrations, code execution, and more.
* **Outputs** — what the tool returns when it's done. Text, links, structured data, or files that get passed back to the agent or displayed to the user.

## Where are Tools most useful?

Tools shine anywhere your agents need to take action beyond conversation:

* **CRM updates**: Automatically create, update, or enrich records in HubSpot, Salesforce, and other systems
* **Email and messaging**: Send emails, Slack messages, or notifications as part of a workflow
* **Web search and scraping**: Pull live information from the web to inform agent decisions
* **Data processing**: Transform, filter, or analyze data with code steps or LLM prompts
* **Third-party APIs**: Connect to any external service — payment processors, marketing platforms, internal systems, and more

## How to get the most from your Tools?

1. **Keep tools focused**: Each tool should do one thing well. Break complex workflows into smaller, composable tools.
2. **Write clear descriptions**: Your agent uses the tool's name and description to decide when to use it — make them specific.
3. **Define inputs carefully**: Use descriptive input names and set sensible defaults so agents pass the right data.
4. **Test step by step**: Run individual steps as you build to catch issues early instead of debugging the whole chain.
5. **Reuse and share**: Build tools once, then give them to multiple agents or share with your team via the Marketplace.

## Frequently asked questions (FAQs)

<AccordionGroup>
  <Accordion title="Do I need coding knowledge to build a tool?">
    No. The Tool Builder is a no-code interface where you chain steps together visually. If you need custom logic, you can add a code step with Python, but it's entirely optional.
  </Accordion>

  <Accordion title="What's the difference between a tool and an agent?">
    An agent thinks, plans, and decides what to do. A tool is a specific action the agent can take — like calling an API or sending an email. Agents use tools to get work done.
  </Accordion>

  <Accordion title="Can I use the same tool across multiple agents?">
    Yes. Tools are reusable. Build a tool once and assign it to as many agents as you like.
  </Accordion>

  <Accordion title="How do I debug a tool that isn't working?">
    Use the **Logs** tab in the Tool Builder to review past executions. You can see exactly what each step received and returned, making it easy to pinpoint where things went wrong.
  </Accordion>

  <Accordion title="Can I call external APIs from a tool?">
    Yes. You can add an API step to call any REST endpoint, pass headers and parameters, and use the response in subsequent steps.
  </Accordion>
</AccordionGroup>

***

## Ready to get started with Tools?

<CardGroup cols={2}>
  <Card title="Build a Tool" icon="hammer" href="/build/tools/create-a-tool">
    Follow our guide to create your first tool step by step
  </Card>

  <Card title="Tool Style Guide" icon="palette" href="/build/tools/customize-tool/tool-style-guide">
    Learn best practices for building effective tools
  </Card>
</CardGroup>