Configure file operations

const sentinel = "BA_DURABLE_42";
const sandbox = await client.sandboxes.create({});
const agent = await client.agents.get(agentId);
const tools = agent.tools.includes("file_operation_sandbox")
  ? agent.tools
  : [...agent.tools, "file_operation_sandbox" as const];

await client.agents.update(agentId, { sandboxId: sandbox.id, tools });

const writeTurn = await client.chat({
  agentId,
  message: { id: crypto.randomUUID(), role: "user", parts: [{
    type: "text", text: `Use write to create durable.txt containing exactly ${sentinel}. Do not publish it.`,
  }] },
});
for await (const _chunk of writeTurn.toUIMessageStream()) { /* drain */ }

const readTurn = await client.chat({
  agentId,
  message: { id: crypto.randomUUID(), role: "user", parts: [{
    type: "text", text: "Use read to read durable.txt, then summarize.",
  }] },
});
const sessionId = await readTurn.sessionId;
for await (const _chunk of readTurn.toUIMessageStream()) { /* drain */ }
const { data } = await client.sessions.messages(agentId, sessionId);
const read = data.flatMap((message) => message.parts).find((part) =>
  part.type === "tool-read" && part.state === "output-available")?.output;
if (typeof read !== "object" || read === null || !("path" in read) || !("content" in read)
  || read.path !== "/workspace/durable.txt" || read.content !== sentinel) throw new Error("Persistence check failed");