# Choose the building block your workflow needs

Understand tools, resources, prompts, Agent Skills, recipes and optional MCP extensions before choosing a client workflow.

Canonical: https://aroai.com/docs/capabilities/

## Tool

An individual capability an AI client can call with a defined input schema. Tool pages describe the purpose, inputs, source, access requirements and result.

## Resource

Reference content or data a supporting client can read and bring into context. Reading a resource is different from executing a tool.

## Prompt

A predefined task template a client may offer to the user. Availability depends on host feature support and permissions.

## Agent Skill

A reusable workflow package containing instructions and, where needed, supporting files. The host controls how it loads and uses the package.

## Recipe

An Aroai implementation guide that combines setup, inputs, tools or skills, expected results and review steps. It is a publishing format, not a separate MCP primitive.

## Check the complete combination

Review the Aroai server and catalog version, client product and version, authentication method, protocol revision and any extensions a workflow needs. Tool annotations are hints; server authorization enforces access.