Fulfill input rounds and listen statelessly A modern operation may request roots, sampling, or elicitation before it completes; generated clients handle roots and host-callback elicitation while leaving sampling undeclared. Modern notifications arrive through a fresh subscriptions/listen POST. cpp academy academy/topics/mcp-modern-roundtrips-listening website/content-src/academy/course.mjs academy Fulfill input rounds and listen statelessly
Unit 9 · Connect to external tools and data

Fulfill input rounds and listen statelessly

A modern operation may request roots, sampling, or elicitation before it completes; generated clients handle roots and host-callback elicitation while leaving sampling undeclared. Modern notifications arrive through a fresh subscriptions/listen POST.

startListening()10 focused minutesNot started
Unit example (nearest native match)

See the idea in context

auto transport = std::make_shared<axllm::AxMCPStreamableHTTPTransport>(endpoint);
auto mcp = std::make_shared<axllm::AxMCPClient>(transport, axllm::object({{"namespace", "inventory"}}));
axllm::AxExecutionContext context({mcp});
auto program = axllm::ax("request:string -> answer:string");
context.attach(program);
axllm::OpenAICompatibleClient llm(axllm::object({
  {"api_key", key}, {"model", "gpt-5.4-mini"},
}));
auto catalog = mcp->inspect_catalog();
std::cout << "MCP catalog: " << axllm::Core::iter(catalog.tools).size()
          << " tools, " << axllm::Core::iter(catalog.resources).size()
          << " resources\n";
std::cout << axllm::stringify(program.forward(
  llm, axllm::object({{"request", "Reindex inventory."}})
)) << "\n";
mcp->close();
Run itIn your own project
include(FetchContent)
FetchContent_Declare(axllm GIT_REPOSITORY https://github.com/ax-llm/ax GIT_TAG main SOURCE_SUBDIR packages/cpp)
FetchContent_MakeAvailable(axllm)
target_link_libraries(your_app PRIVATE axllm::axllm)

#include <axllm/axllm.hpp>

auto llm = axllm::ai("openai", axllm::object({{"apiKey", std::getenv("OPENAI_API_KEY")}}));
auto classify = axllm::ax("review:string -> sentiment:class \"positive, negative, neutral\"");

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/native_mcp_tools.cpp
Active practice

Show that you can use it

Answer 2 in a row to learn this · attempt 1
Keep exploring

Source-backed follow-up