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

# Sandboxes for SWE agents

Researching SWE agents is hard: there are thousands of heavy-weight environments, setup is slow, and reproducibility is fragile. Sandboxes provides a branchable, VM-isolated sandbox designed for rapid experimentation across thousands of SWE environments — over 7,000 are preloaded out of the box.

## Purpose-built for SWE agent research

* Thousands of ready-to-run SWE environments, so you can benchmark agents with minimal infrastructure setup.
* Git-like branching to try multiple patches or strategies in parallel from the same checkpoint, then keep only the winning branch: MCTS, beam search, rollbacks, value-function estimation.
* VM-level isolation with per-run metrics to keep generated code contained and experiments auditable.

## Environment catalog

Pick from the preloaded catalog rather than building or pulling terabytes of images yourself. What's included now:

* [SWE-bench Verified](https://huggingface.co/datasets/princeton-nlp/SWE-bench_Verified)
* [SWE-rebench](https://huggingface.co/datasets/nebius/SWE-rebench/viewer/default/filtered)
* [SWE-rebench-V2](https://huggingface.co/datasets/nebius/SWE-rebench-V2)

## Integrations

<Columns cols={2}>
  <Card title="Contree CLI" icon="terminal" href="/sandboxes/cli">
    Terminal-first agent workflows, scripted runs, session branching, and filesystem inspection.
  </Card>

  <Card title="Contree SDK" icon="python" href="/sandboxes/sdk">
    Integrate your own agent via contree-sdk.
  </Card>

  <Card title="Contree MCP" icon="plug" href="/sandboxes/mcp">
    Plug sandboxes into AI assistants that speak the Model Context Protocol.
  </Card>
</Columns>