Unit 10 · React safely to live events

Resume only the task that owns the event

You let input-required and terminal events resume only their identity-scoped owning continuation. Recorded envelopes make that boundary testable without a live server.

10 focused minutesNot started

Worked example

See the idea in context

axllm::AxEventTarget target;
target.id = "reindex-flow";
target.waitFor = axllm::array({axllm::object({
  {"kind", "mcp.task"}, {"value", "taskKey"},
  {"metadata", axllm::object({{"taskId", task_id}})},
})});
target.mapInput = [](const axllm::AxEventEnvelope& event,
                     const axllm::AxEventContinuation* continuation) {
  return axllm::object({{"taskId", continuation
    ? axllm::Core::get(continuation->metadata, "taskId")
    : axllm::Core::get(event.data, "taskId")}});
};
target.invoke = invoke_flow;
axllm::AxEventRuntime runtime({
  axllm::AxEventRoute{"task-start", "wake", start_match, "reindex-flow"},
  axllm::AxEventRoute{"task-resume", "resume", resume_match, "reindex-flow"},
});
runtime.register_target(std::move(target)).start();

Run itIn your own project

cmake_minimum_required(VERSION 3.20)
project(ax_quick_start LANGUAGES CXX)
set(CMAKE_CXX_STANDARD 17)

include(FetchContent)
FetchContent_Declare(axllm GIT_REPOSITORY https://github.com/ax-llm/ax GIT_TAG main SOURCE_SUBDIR packages/cpp)
FetchContent_MakeAvailable(axllm)

add_executable(quick_start quick_start.cpp)
target_link_libraries(quick_start PRIVATE axllm::axllm)

#include <axllm/axllm.hpp>
#include <cstdlib>
#include <iostream>

int main() {
  auto llm = axllm::ai("openai", axllm::object({{"apiKey", std::getenv("OPENAI_API_KEY")}}));
  auto classify = axllm::ax("review:string -> sentiment:class \"positive, negative, neutral\"");
  auto result = classify.forward(*llm, axllm::object({
    {"review", "Useful and boring in the best way."}
  }));

  auto sentiment = axllm::Core::get(result, "sentiment");
  std::cout << "sentiment: " << std::get<std::string>(sentiment.data) << "\n";
}

Set OPENAI_APIKEY in your environment before running provider-backed code.

In the ax repo

From a clone of the ax repo:

npm run example -- cpp src/examples/cpp/mcp/resource_wake_agent.cpp

Active practice

Show that you can use it

Answer 2 in a row to learn this · attempt 1

Keep exploring

See the idea in context

Show that you can use it

Source-backed follow-up