Teach builder sandbox rootfs capture

agent_builder/skills/a2apack-agent-authoring/SKILL.md

@@ -130,9 +130,10 @@ If a skill calls `ctx.workspace_backend()` or `ctx.workspace`, declare
 
 If a skill runs code, renderers, converters, or data tools that create
 downloadable files, run them through `await ctx.workspace_shell(...)` or
-`await ctx.workspace_python(...)` and make the command write under
-`/workspace/outputs/...`. In-process subprocesses write inside the agent pod,
-not the caller's mounted workspace.
+`await ctx.workspace_python(...)`. The sandbox persists `/workspace` writes
+directly and mirrors changed files elsewhere in the guest rootfs under
+`outputs/rootfs-captures/...`. In-process subprocesses write inside the agent
+pod, not the caller's mounted or rootfs-captured workspace.
 
 When invoking an inner DeepAgents graph, pass
 `config={"recursion_limit": 500}` to `graph.ainvoke(...)` or