---
title: Ontology
description: Objects, Queries, Mutations, and Actions, the Resources that agents and Apps use.
---

A Workspace's **Ontology** is its Objects, Queries, Mutations, and Actions: the Resources that agents and Apps use. It describes the things a business tracks and the operations allowed on them.

## Objects

An **Object** defines the fields and links of the records a customer tracks, such as the customer's own customers.

## Functions

A **Function** is a Query, a Mutation, or an Action: TypeScript code that Tractorbeam runs with its bindings. Each kind may do different things:

- A **Query** reads data by running SQL.
- A **Mutation** changes Tables in one Commit. It has no network access.
- An **Action** does work that reaches other systems or needs more than one Commit.

## Invocations

An **invocation** is a Function invoked once, with one input, for one principal. An invocation of an Action is an Action invocation. A failed attempt can be retried, so one invocation can have several attempts.