Generation Generation — C++ examples backed by real provider calls. cpp examples examples/generation src/examples/cpp/generation example Generation

These C++ examples are real runnable files. Edit the source file first; this page is rebuilt from the checked-in example and its metadata header.

C++ Typed Generation

Runs a small typed generation program against OpenAI.

C++
#include "axllm/axllm.hpp"
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <sstream>


int main() {
  const char* key = std::getenv("OPENAI_API_KEY");
  if (key == nullptr || std::string(key).empty()) key = std::getenv("OPENAI_APIKEY");
  if (key == nullptr || std::string(key).empty()) {
    std::cerr << "Set OPENAI_API_KEY or OPENAI_APIKEY to run this example.\n";
    return 2;
  }
  const char* model = std::getenv("AX_OPENAI_MODEL");
  axllm::OpenAICompatibleClient client(axllm::object({
      {"api_key", key},
      {"model", model == nullptr || std::string(model).empty() ? "gpt-5.4-mini" : model},
      {"model_config", axllm::object({{"temperature", 0}})},
  }));
  axllm::AxGen program = axllm::ax("question:string -> answer:string");
  axllm::Value output = program.forward(client, axllm::object({{"question", "In one sentence, explain Ax as a language-agnostic LLM programming library."}}));
  std::cout << axllm::stringify(output) << "\n";
}

C++ Structured Extraction

Extracts structured fields and labels from support text with OpenAI.

C++
#include "axllm/axllm.hpp"
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <sstream>


int main() {
  const char* key = std::getenv("OPENAI_API_KEY");
  if (key == nullptr || std::string(key).empty()) key = std::getenv("OPENAI_APIKEY");
  if (key == nullptr || std::string(key).empty()) {
    std::cerr << "Set OPENAI_API_KEY or OPENAI_APIKEY to run this example.\n";
    return 2;
  }
  const char* model = std::getenv("AX_OPENAI_MODEL");
  axllm::OpenAICompatibleClient client(axllm::object({
      {"api_key", key},
      {"model", model == nullptr || std::string(model).empty() ? "gpt-5.4-mini" : model},
      {"model_config", axllm::object({{"temperature", 0}})},
  }));
  axllm::AxGen program = axllm::ax("ticket:string -> priority:class \"high, normal, low\", summary:string, labels:string[]");
  axllm::Value output = program.forward(client, axllm::object({{"ticket", "Checkout has failed for enterprise customers since 09:00. Support wants a concise summary and tags."}}));
  std::cout << axllm::stringify(output) << "\n";
}

C++ Signature Constraints

Builds native constrained fields and runs the signature with OpenAI.

C++
#include "axllm/axllm.hpp"
#include <cstdlib>
#include <iostream>

axllm::Value field(const char* name, const char* title, axllm::Value type) {
  return axllm::Core::record_new(
      "Field", axllm::object({{"name", name}, {"title", title}, {"type", type}}));
}

int main() {
  const char* key = std::getenv("OPENAI_API_KEY");
  if (key == nullptr || std::string(key).empty()) key = std::getenv("OPENAI_APIKEY");
  if (key == nullptr || std::string(key).empty()) {
    std::cerr << "Set OPENAI_API_KEY or OPENAI_APIKEY to run this example.\n";
    return 2;
  }
  const char* model = std::getenv("AX_OPENAI_MODEL");
  axllm::OpenAICompatibleClient client(axllm::object({
      {"api_key", key},
      {"model", model == nullptr || std::string(model).empty() ? "gpt-5.4-mini" : model},
      {"model_config", axllm::object({{"temperature", 0}})},
  }));

  axllm::Value signature = axllm::Core::record_new(
      "AxSignature",
      axllm::object({
          {"description", "Extract a constrained restaurant booking"},
          {"inputs",
           axllm::array({
               field("requestText", "Request Text",
                     axllm::Core::record_new(
                         "FieldType",
                         axllm::object({{"name", "string"}, {"minLength", 10}, {"maxLength", 500}}))),
               field("contactEmail", "Contact Email",
                     axllm::Core::record_new(
                         "FieldType", axllm::object({{"name", "string"}, {"format", "email"}}))),
           })},
          {"outputs",
           axllm::array({
               field("partySize", "Party Size",
                     axllm::Core::record_new(
                         "FieldType",
                         axllm::object({{"name", "number"}, {"minimum", 1}, {"maximum", 12}}))),
               field("bookingCode", "Booking Code",
                     axllm::Core::record_new(
                         "FieldType",
                         axllm::object({
                             {"name", "string"},
                             {"pattern", "^[A-Z]{3}-\\d{4}$"},
                             {"patternDescription", "Must look like ABC-1234"},
                         }))),
           })},
      }));
  axllm::Core::validate_signature(signature);
  axllm::AxGen program = axllm::ax(signature);
  axllm::Value output = program.forward(
      client,
      axllm::object({
          {"requestText", "Book dinner for four people under the name Ada Lovelace."},
          {"contactEmail", "ada@example.com"},
      }));
  std::cout << axllm::stringify(output) << "\n";
}

Centralized Usage Observer

Attributes every completed model call to a tenant, user, and request from one global observer.

C++
#include "axllm/axllm.hpp"

#include <chrono>
#include <cstdlib>
#include <iostream>
#include <string>
#include <vector>

int main() {
  const char* api_key = std::getenv("OPENAI_API_KEY");
  if (api_key == nullptr || std::string(api_key).empty()) api_key = std::getenv("OPENAI_APIKEY");
  if (api_key == nullptr || std::string(api_key).empty()) {
    std::cerr << "Set OPENAI_API_KEY or OPENAI_APIKEY to run this example.\n";
    return 2;
  }
  const char* configured_model = std::getenv("AX_OPENAI_MODEL");
  std::string model =
      configured_model == nullptr || std::string(configured_model).empty()
          ? "gpt-5.4-mini"
          : configured_model;

  std::vector<axllm::AxUsageEvent> events;
  axllm::set_usage_observer(
      [&events](axllm::AxUsageEvent event) { events.push_back(std::move(event)); });
  axllm::OpenAICompatibleClient client(axllm::object({
      {"api_key", api_key},
      {"model", model},
      {"usageContext",
       axllm::object({
           {"tenantId", "tenant-42"},
           {"feature", "support-chat"},
           {"attributes", axllm::object({{"environment", "example"}})},
       })},
  }));
  client.chat(
      axllm::object({
          {"chat_prompt",
           axllm::array({
               axllm::object({{"role", "user"}, {"content", "Reply with one short greeting."}}),
           })},
      }),
      axllm::object({
          {"usageContext",
           axllm::object({
               {"userId", "user-7"},
               {"requestId",
                "request-" +
                    std::to_string(
                        std::chrono::steady_clock::now().time_since_epoch().count())},
           })},
      }));
  axllm::set_usage_observer({});
  std::cout << axllm::stringify(axllm::Value(axllm::Array(events.begin(), events.end())))
            << "\n";
}

C++ Contextual Generation

Answers from supplied context and returns compact citations with OpenAI.

C++
#include "axllm/axllm.hpp"
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <sstream>


int main() {
  const char* key = std::getenv("OPENAI_API_KEY");
  if (key == nullptr || std::string(key).empty()) key = std::getenv("OPENAI_APIKEY");
  if (key == nullptr || std::string(key).empty()) {
    std::cerr << "Set OPENAI_API_KEY or OPENAI_APIKEY to run this example.\n";
    return 2;
  }
  const char* model = std::getenv("AX_OPENAI_MODEL");
  axllm::OpenAICompatibleClient client(axllm::object({
      {"api_key", key},
      {"model", model == nullptr || std::string(model).empty() ? "gpt-5.4-mini" : model},
      {"model_config", axllm::object({{"temperature", 0}})},
  }));
  axllm::AxGen program = axllm::ax("context:string, question:string -> answer:string, citations:string[]");
  axllm::Value output = program.forward(client, axllm::object({{"context", "Ax uses signatures, ai(), ax(), agent(), flow(), and optimize()."}, {"question", "How should a new developer think about Ax?"}}));
  std::cout << axllm::stringify(output) << "\n";
}

C++ Adaptive Provider Balancing

Routes equivalent chat traffic using shared reliability, latency, and cost statistics.

C++
#include "axllm/axllm.hpp"

#include <cstdlib>
#include <iostream>
#include <memory>
#include <vector>

int main() {
  const char* raw_key = std::getenv("OPENAI_API_KEY");
  if (raw_key == nullptr || std::string(raw_key).empty()) raw_key = std::getenv("OPENAI_APIKEY");
  if (raw_key == nullptr || std::string(raw_key).empty()) {
    std::cerr << "Set OPENAI_API_KEY or OPENAI_APIKEY to run this example.\n";
    return 2;
  }
  const std::string model = std::getenv("AX_OPENAI_MODEL") == nullptr ? "gpt-5.4-mini" : std::getenv("AX_OPENAI_MODEL");
  auto primary = std::make_shared<axllm::OpenAICompatibleClient>(axllm::object({{"api_key", raw_key}, {"model", model}}));
  auto backup = std::make_shared<axllm::OpenAICompatibleClient>(axllm::object({{"api_key", raw_key}, {"model", model}}));

  auto store = std::make_shared<axllm::AxInMemoryBalancerStatsStore>();
  std::vector<std::string> route_keys{"openai-primary", "openai-backup"};
  std::vector<std::string> events;
  auto strategy = std::make_shared<axllm::AxBalancerAdaptiveStrategy>();
  strategy->deadline_ms = 6'000;
  strategy->bad_outcome_cost = 0.02;
  strategy->expected_tokens = axllm::object({{"promptTokens", 1'200}, {"completionTokens", 300}});
  strategy->name_space = "support-summary-v1";
  strategy->route_key = [route_keys](const std::shared_ptr<axllm::AxAIService>&, std::size_t index) { return route_keys.at(index); };
  strategy->slice = [](axllm::Value context) { return axllm::Core::truthy(axllm::Core::get(axllm::Core::get(context, "options"), "stream")) ? "streaming" : "interactive"; };
  strategy->stats_store = store;
  strategy->on_routing_event = [&events](axllm::Value event) { events.push_back(axllm::display(axllm::Core::get(event, "type"))); };

  axllm::AxBalancerOptions options;
  options.strategy = strategy;
  axllm::AxBalancer balancer({primary, backup}, options);
  auto response = balancer.chat(axllm::object({{"model", model}, {"chat_prompt", axllm::array({axllm::object({{"role", "user"}, {"content", "Summarize why shared routing state matters."}})})}}));
  std::cout << axllm::stringify(response) << "\n" << events.size() << " routing events\n";
}
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