> For the complete documentation index, see [llms.txt](/llms.txt).
> A full single-fetch corpus is available at [llms-full.txt](/llms-full.txt).
---
title: Build with AGNT5
description: Define workflows, functions, agents, prompts, webhooks, and approval steps before you deploy.
last_verified: 2026-06-10
---

Build is where you define the application code AGNT5 runs. A **[workflow](/docs/build/workflows.md)** is a durable program made of checkpointed steps, an **[agent](/docs/build/agents.md)** is a reasoning loop that can call tools, and a **[function](/docs/build/functions.md)** wraps deterministic work with retries and trace visibility. Use these pages when you are shaping behavior locally before creating a **[deployment](/docs/run/deploying.md)**.

## Build guides

<LinkCardGroup compact>
  <LinkCard
    title="Functions"
    href="/docs/build/functions"
    icon="code"
    description="Wrap deterministic work in retryable, observable units."
  />
  <LinkCard
    title="Workflows"
    href="/docs/build/workflows"
    icon="refresh"
    description="Compose multi-step programs with durable state and checkpointed execution."
  />
  <LinkCard
    title="Agents"
    href="/docs/build/agents"
    icon="user"
    description="Define reasoning loops that call tools and keep state across a run."
  />
  <LinkCard
    title="Tools"
    href="/docs/build/tools"
    icon="settings"
    description="Expose capabilities an agent can call during its loop."
  />
  <LinkCard
    title="Prompts"
    href="/docs/build/prompts"
    icon="chat"
    description="Keep prompt text versioned and runnable from code."
  />
  <LinkCard
    title="Human in the Loop"
    href="/docs/build/human-in-the-loop"
    icon="eye"
    description="Pause a workflow until a person approves or supplies input."
  />
  <LinkCard
    title="Webhooks"
    href="/docs/build/webhooks"
    icon="bolt"
    description="Receive external events and route them into AGNT5 workflows."
  />
  <LinkCard
    title="Model Context Protocol"
    href="/docs/build/mcp"
    icon="plug"
    description="Import external MCP tools or expose AGNT5 primitives to MCP clients."
  />
  <LinkCard
    title="Local development"
    href="/docs/build/local-development"
    icon="terminal"
    description="Run your project with agnt5 dev and trigger it from Studio, the CLI, or the API."
  />
</LinkCardGroup>

Outcome: you have local code that defines the workflow behavior, model calls, external inputs, and approval points AGNT5 will run.

## Next steps



After you understand the Build section, start with the path that matches your current project.

- [Run locally](/docs/build/local-development): Start the worker with `agnt5 dev` and trigger runs from Studio.
- [Define a workflow](/docs/build/workflows): Compose durable steps and checkpointed execution.
- [Deploy the code](/docs/run/deploying): Move the worker into an AGNT5 environment.