---
title: Work with DigitalOcean Harness Runtime Sessions (public)
description: Attach to running sessions, move files in and out, reach ports inside the sandbox, and checkpoint or fork a session.
product: Managed Agents
url: https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/how-to/work-with-sessions/
last_updated: "2026-10-06"
---

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# Work with DigitalOcean Harness Runtime Sessions (public)

Generated on 26 Oct 2026

DigitalOcean Harness Runtime provides managed, hardware-isolated microVM sandboxes with built-in tools such as Chromium to run harnesses and execute arbitrary code. Rich lifecycle APIs preserve conversational history and working state across sessions, letting you pause, resume, and fork work to control costs and adapt to the nonlinear nature of agentic workflows. Scale complete agents such as Claude Code or use sandboxes independently for code execution, all through the same service. See [What You Can Build](https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/details/what-you-can-build/index.html.md) for example use cases.

[How to Manage DigitalOcean Harness Runtime Sessions](https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/how-to/manage-sessions/index.html.md): List, show, pause, resume, attach, detach, cancel a run, log, and remove Harness Runtime sessions with doctl harness-runtime or the Control Panel.

[How to Connect Through the Codex CLI Proxy](https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/how-to/use-codex-proxy/index.html.md): Start a local doctl proxy so your local Codex CLI drives a hosted Codex session.

[How to Upload and Download Session Files](https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/how-to/transfer-files/index.html.md): Upload files into a sandbox and download agent output to your local machine.

[How to Forward Sandbox Ports](https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/how-to/forward-ports/index.html.md): Open a local tunnel to a port inside a session’s sandbox with doctl harness-runtime port-forward.

[How to Checkpoint, Fork, and Roll Back Sessions](https://docs.digitalocean.com/products/managed-agents/agent-harness-runtime/how-to/checkpoint-fork-rollback-sessions/index.html.md): Save a Harness Runtime session as a checkpoint, then fork it into parallel copies or roll the same session back in place.