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SecondAgent · Agent Mode

SecondAgent is SecondStack’s agentic mode — it appears as the Cowork Agent inside the chat UI. It turns a chat into a working session with an AI coworker: it runs the Claude Code CLI inside an isolated, per-thread Docker sandbox, equipped with Skills for real tasks — reading and writing files, automating a browser, authoring diagrams and office documents, generating images, and remembering context across a session.

create a hello world program in this workspace
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Done. Created and ran hello_world.py — it prints "Hello, World!" as expected.

hello_world.py
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hello_world.py 23 B
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The agent works in its own sandboxed workspace — here creating and running a file, then returning it.

How it runs

Section titled “How it runs”
  • Each agent session runs the Claude Code CLI inside its own Docker sandbox container, tied to a single chat thread, with an isolated workspace.
  • Sandboxes run as a non-root user with baked, read-only tooling, keeping the runtime constrained.
  • Files move in and out of the sandbox through presigned object storage, and generated artifacts are returned to the chat.

Where it runs

Section titled “Where it runs”

SecondAgent supports two runtimes, which administrators can enable independently:

  • Cloud / server runtime — sandboxes run on the platform’s own infrastructure.
  • Local desktop runtime — a companion desktop app (macOS, Windows, Linux) pairs to the platform and runs sandboxes on the user’s own machine and folders.

Skills

Section titled “Skills”

Skills give the agent concrete capabilities. SecondStack ships 18+ built-in Skills, and the set is extensible with your own. They include:

  • File operations — read, write, and manipulate files in the workspace.
  • Browser automation — drive a real browser for research and web tasks.
  • Image generation — create and edit images.
  • Diagram authoring — produce diagrams (for example, draw.io).
  • Office documents — author Word, Excel, PowerPoint, and PDF files.
  • Persistent memory — carry context forward within a session.

Additional Skills can be added per user or overlaid for the whole organization.

Billing

Section titled “Billing”

The agent can run against a Claude subscription (via OAuth) or against API billing through the gateway, depending on the profile an administrator configures.

Section titled “Related”