For AI agents: The documentation index is at https://docs.digitalocean.com/llms.txt. Markdown versions of pages use the same URL with index.html.md in place of the HTML page (for example, append index.html.md to the directory path instead of opening the HTML document).

Harness Runtime provides the following capabilities.

• Agent Adapters: Run coding agents such as Codex, Claude Code, and OpenCode, or general purpose agent frameworks such as LangGraph and Hermes in an isolated sandbox. Describe the agent, sandbox size, variables, permissions, and tools in a YAML environment spec and interact through doctl harness-runtime launch, an optional Codex local proxy, or use the Control Panel to configure and create an environment. Use agent: codex-agentapi to connect an OpenAI Agents API session to a DigitalOcean sandbox through the CLI, PyDo, or an OpenAI webhook controller. See Run an OpenAI Agents API Session.

• Session Lifecycle: Start, attach, list, show, pause, resume, remove, and view logs for sessions. Configure suspend via idle timeout or pause the session manually to preserve workspace state and conversation history while suspending compute. The session resumes on new input when the platform wakes it. You can also create checkpoints to capture the whole machine state from which you can fork a new session or roll back to a prior state

• Permissions: Set a default tool action of allow, ask, or deny. Add explicit rules for shell commands and file paths. You can also validate policies with the policy validation API before starting a session.

• Secrets: When your agent needs credentials (like API keys or tokens), add them as secrets. DigitalOcean stores them securely and injects them into the session when it starts, so the values never appear in the spec file or in logs.

• Files and GitHub: Upload and download workspace files. You can grant GitHub access or declare a personal access token.

• Action Gateway: Declare Action Gateway tools to use.

• Bring-Your-Own-Template (BYOT): Register a team-owned OCI image as a custom sandbox template. DigitalOcean rebases the image onto one of the supported base templates (coding-codex, coding-opencode, coding-hermes, langgraph, or coding-claude-code) in a temporary build microVM. Sessions that name the resulting template start from your image instead of the stock catalog image. See Use a Custom Sandbox Template.

Sandbox Sizes

Each session runs in a sandbox sized by a slug you set with size in the environment spec. Choose the smallest size that fits your workload to keep session compute costs down. If you omit size, the platform uses mars-2vcpu-4gb.

To query the current catalog directly, run:

curl https://api.digitalocean.com/v2/agents/sessions/sandbox/sizes \
  -H "Authorization: Bearer $DIGITALOCEAN_ACCESS_TOKEN"