# Agent bugfix
URL: /docs/playground/agent-bugfix

Load a Pi coding agent into a sandbox, hand it a failing test, and stream every tool call as it debugs and fixes it.



`alineo` runs [Pi](https://pi.ai) coding agents inside sandboxes. You hand the agent a task and
stream back everything it does — text, and every tool call — while it reads files, edits code,
and runs commands inside its own container.

This workflow plants a buggy `fib.py` with a failing test, hands it to a `python-data` agent,
and streams the session until the agent stops. Then it runs the test suite independently to
check the agent's work.

<WorkflowRunner workflow="agent-bugfix" />

## What just happened [#what-just-happened]

* `Alineo.load(pythonDataSpec)` booted an agent — a sandbox with Pi installed and configured.
* `agent.prompt(task)` returned an event stream. Each `tool_start` / `tool_end` is the agent
  running a real command or file edit inside its sandbox; `text` is the model's narration.
* The verify step ran `pytest` ourselves — never take the agent's "all green" on faith.
* `agent.close()` ended the Pi session and deleted the sandbox.

The [AI Agent Bugfix](/docs/cookbooks/ai-agent-bugfix) cookbook adds an independent verifier
agent and a structured verdict. For streaming mechanics, see
[Streaming](/docs/agent/getting-started/streaming).