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

# Esper CLI

> Command-line access to Esper's operator workflows.

## What the Esper CLI does

The Esper CLI enables:

* Workspace initialization and authentication
* Builder resource creation and updates
* Policy deployment and management
* Results inspection
* Hybrid runtime orchestration, including `esper sync`, `esper capture`, and `esper run`

## Installation

```bash theme={null}
# Install the latest Esper CLI
curl --proto '=https' --tlsv1.2 -fsSL https://sh.esperr.com/ | sh

# Install a specific version
curl --proto '=https' --tlsv1.2 -fsSL https://sh.esperr.com/ | sh -s -- --version 0.10.0
```

Use a specific version when you need a reproducible install or when pinning
the CLI version for a deployment environment.

## Getting started

Initialize the local workspace with an API key and tenant:

```bash theme={null}
esper init \
  --api-base https://api.esperr.com \
  --api-key <secret> \
  --tenant-id <tenant-id>
```

The CLI stores the API key in `~/.esper/config.yaml` and uses it for
authenticated API calls. Operators who need to discover or rotate keys can use
`esper auth login --token <jwt>` followed by `esper keys list`.

## Learn more

* [Configuration](./configuration) - Local workspace and credential management
* [Authentication](./authentication) - Authorization workflows and token handling

### Commands

The CLI provides comprehensive commands for managing Esper resources:

* [Actions](./action) - Define semantic traffic behaviors
* [Entities](./entity) - Establish identity semantics
* [Mitigations](./mitigation) - Configure response behaviors
* [Policies](./policy) - Create and manage evaluation rules
* [Hybrid Runtime](./hybrid) - Local capture and enforcement
* [Results](./results) - View analytics and metrics

<Tip>
  **Choosing a Deployment Mode**

  If you are deciding between Esper Cloud and customer-hosted hybrid runtime, read the [Operation Modes](../intro#operation-modes) section in the overview before choosing a deployment path.
</Tip>