Transactions for AI agents.

r = client.ExecuteStep(pb.ExecuteStepRequest(
    transaction_id=tx, step_id=next_step,
    tool_name=call.tool, arguments_json=json.dumps(call.args),
))

if r.status == pb.STEP_STATUS_ROLLBACK_TRIGGERED:
    agent.rewind(r.rollback_to_step, reset_context=r.context_reset)
    system_prompt.constraints = list(r.constraints)   # one-line Clean Hints

next_step = r.next_step_id

const r = await executeStep({
  transaction_id,
  step_id: nextStep,
  tool_name: "record.insert",
  arguments_json: JSON.stringify({ table: "invoices", fields: { customer_id: "${steps.2.value}" } }),
});

if (r.status === "STEP_STATUS_ROLLBACK_TRIGGERED") {
  console.log(r.strategy, r.clean_hint); // DEPENDENCY_JUMP, "Hint: Foreign key constraint failed…"
}
nextStep = r.next_step_id;

let tx = engine.begin("billing-agent", Default::default(), None).await?.tx_id;

let outcome = engine.execute_step(StepRequest {
    tx_id: tx.clone(),
    step_id: 1,
    tool_name: "fs.write".into(),
    arguments_json: r#"{"path":"drafts/inv-1.json","contents":"{}"}"#.into(),
    raw_context: String::new(),
}).await?;

engine.commit(&tx).await?; // publishes state, then dispatches staged emails

grpcurl -plaintext -d '{"agent_id":"quickstart"}' \
  127.0.0.1:50051 agenttx.v1.AgentTxService/BeginTransaction

grpcurl -plaintext -d @ 127.0.0.1:50051 agenttx.v1.AgentTxService/ExecuteStep <<EOF
{ "transaction_id": "$TX", "step_id": 1, "tool_name": "kv.put",
  "arguments_json": "{\"key\":\"customer\",\"value\":\"c-1\"}" }
EOF