diff --git a/src/app/editor/editor_manager.cc b/src/app/editor/editor_manager.cc
index d668ab9a..52267cfc 100644
--- a/src/app/editor/editor_manager.cc
+++ b/src/app/editor/editor_manager.cc
@@ -383,6 +383,7 @@ void EditorManager::Initialize(gfx::IRenderer* renderer,
     *output_path = result->file_path;
     return absl::OkStatus();
   };
+#ifdef YAZE_AI_RUNTIME_AVAILABLE
   multimodal_callbacks.send_to_gemini =
       [this](const std::filesystem::path& image_path,
              const std::string& prompt) -> absl::Status {
@@ -417,6 +418,14 @@ void EditorManager::Initialize(gfx::IRenderer* renderer,
 
     return absl::OkStatus();
   };
+#else
+  multimodal_callbacks.send_to_gemini =
+      [](const std::filesystem::path&, const std::string&) -> absl::Status {
+    return absl::FailedPreconditionError(
+        "Gemini AI runtime is disabled in this build");
+  };
+#endif
+
   agent_editor_.GetChatWidget()->SetMultimodalCallbacks(multimodal_callbacks);
 
   // Set up Z3ED command callbacks for proposal management
diff --git a/src/cli/service/agent/proposal_executor.cc b/src/cli/service/agent/proposal_executor.cc
index 55b4c7c0..05c919a4 100644
--- a/src/cli/service/agent/proposal_executor.cc
+++ b/src/cli/service/agent/proposal_executor.cc
@@ -1,5 +1,21 @@
 #include "cli/service/agent/proposal_executor.h"
 
+#ifndef YAZE_AI_RUNTIME_AVAILABLE
+
+#include "absl/status/status.h"
+
+namespace yaze::cli::agent {
+
+absl::StatusOr<ProposalCreationResult> CreateProposalFromAgentResponse(
+    const ProposalCreationRequest&) {
+  return absl::FailedPreconditionError(
+      "AI runtime features are disabled in this build");
+}
+
+}  // namespace yaze::cli::agent
+
+#else  // YAZE_AI_RUNTIME_AVAILABLE
+
 #include <filesystem>
 #include <sstream>
 #include <utility>
@@ -180,3 +196,5 @@ absl::StatusOr<ProposalCreationResult> CreateProposalFromAgentResponse(
 }  // namespace agent
 }  // namespace cli
 }  // namespace yaze
+
+#endif  // YAZE_AI_RUNTIME_AVAILABLE
diff --git a/src/cli/service/ai/gemini_ai_service.h b/src/cli/service/ai/gemini_ai_service.h
index 37483c76..19ad4b80 100644
--- a/src/cli/service/ai/gemini_ai_service.h
+++ b/src/cli/service/ai/gemini_ai_service.h
@@ -7,7 +7,10 @@
 #include "absl/status/status.h"
 #include "absl/status/statusor.h"
 #include "cli/service/ai/ai_service.h"
+
+#ifdef YAZE_AI_RUNTIME_AVAILABLE
 #include "cli/service/ai/prompt_builder.h"
+#endif
 
 namespace yaze {
 namespace cli {
@@ -27,6 +30,8 @@ struct GeminiConfig {
   explicit GeminiConfig(const std::string& key) : api_key(key) {}
 };
 
+#ifdef YAZE_AI_RUNTIME_AVAILABLE
+
 class GeminiAIService : public AIService {
  public:
   explicit GeminiAIService(const GeminiConfig& config);
@@ -65,6 +70,37 @@ class GeminiAIService : public AIService {
   PromptBuilder prompt_builder_;
 };
 
+#else  // !YAZE_AI_RUNTIME_AVAILABLE
+
+class GeminiAIService : public AIService {
+ public:
+  explicit GeminiAIService(const GeminiConfig&) {}
+  void SetRomContext(Rom*) override {}
+  absl::StatusOr<AgentResponse> GenerateResponse(
+      const std::string& prompt) override {
+    return absl::FailedPreconditionError(
+        "Gemini AI runtime is disabled (prompt: " + prompt + ")");
+  }
+  absl::StatusOr<AgentResponse> GenerateResponse(
+      const std::vector<agent::ChatMessage>&) override {
+    return absl::FailedPreconditionError(
+        "Gemini AI runtime is disabled");
+  }
+  absl::Status CheckAvailability() {
+    return absl::FailedPreconditionError(
+        "Gemini AI runtime is disabled");
+  }
+  void EnableFunctionCalling(bool) {}
+  std::vector<std::string> GetAvailableTools() const { return {}; }
+  absl::StatusOr<AgentResponse> GenerateMultimodalResponse(
+      const std::string&, const std::string&) {
+    return absl::FailedPreconditionError(
+        "Gemini AI runtime is disabled");
+  }
+};
+
+#endif  // YAZE_AI_RUNTIME_AVAILABLE
+
 }  // namespace cli
 }  // namespace yaze
 
diff --git a/src/cli/service/ai/ollama_ai_service.h b/src/cli/service/ai/ollama_ai_service.h
index 4c3828f7..9d7bbe81 100644
--- a/src/cli/service/ai/ollama_ai_service.h
+++ b/src/cli/service/ai/ollama_ai_service.h
@@ -9,7 +9,10 @@
 #include "absl/status/statusor.h"
 #include "absl/time/time.h"
 #include "cli/service/ai/ai_service.h"
+
+#ifdef YAZE_AI_RUNTIME_AVAILABLE
 #include "cli/service/ai/prompt_builder.h"
+#endif
 
 namespace yaze {
 namespace cli {
@@ -17,7 +20,7 @@ namespace cli {
 // Ollama configuration for local LLM inference
 struct OllamaConfig {
   std::string base_url = "http://localhost:11434";  // Default Ollama endpoint
-  std::string model = "qwen2.5-coder:7b";           // Recommended for code generation
+  std::string model = "qwen2.5-coder:0.5b";         // Lightweight default with tool-calling
   float temperature = 0.1;                          // Low temp for deterministic commands
   int max_tokens = 2048;                            // Sufficient for command lists
   std::string system_prompt;                        // Injected from resource catalogue
@@ -30,6 +33,8 @@ struct OllamaConfig {
   std::vector<std::string> favorite_models;
 };
 
+#ifdef YAZE_AI_RUNTIME_AVAILABLE
+
 class OllamaAIService : public AIService {
  public:
   explicit OllamaAIService(const OllamaConfig& config);
@@ -69,6 +74,44 @@ class OllamaAIService : public AIService {
   absl::StatusOr<std::string> ParseOllamaResponse(const std::string& json_response);
 };
 
+#else  // !YAZE_AI_RUNTIME_AVAILABLE
+
+class OllamaAIService : public AIService {
+ public:
+  struct ModelInfo {
+    std::string name;
+    std::string digest;
+    std::string family;
+    std::string parameter_size;
+    std::string quantization_level;
+    uint64_t size_bytes = 0;
+    absl::Time modified_at = absl::InfinitePast();
+  };
+
+  explicit OllamaAIService(const OllamaConfig&) {}
+  void SetRomContext(Rom*) override {}
+  absl::StatusOr<AgentResponse> GenerateResponse(
+      const std::string&) override {
+    return absl::FailedPreconditionError(
+        "Ollama AI runtime is disabled");
+  }
+  absl::StatusOr<AgentResponse> GenerateResponse(
+      const std::vector<agent::ChatMessage>&) override {
+    return absl::FailedPreconditionError(
+        "Ollama AI runtime is disabled");
+  }
+  absl::Status CheckAvailability() {
+    return absl::FailedPreconditionError(
+        "Ollama AI runtime is disabled");
+  }
+  absl::StatusOr<std::vector<ModelInfo>> ListAvailableModels() {
+    return absl::FailedPreconditionError(
+        "Ollama AI runtime is disabled");
+  }
+};
+
+#endif  // YAZE_AI_RUNTIME_AVAILABLE
+
 }  // namespace cli
 }  // namespace yaze
 
diff --git a/src/cli/service/ai/service_factory.cc b/src/cli/service/ai/service_factory.cc
index 4d944396..b22b0a32 100644
--- a/src/cli/service/ai/service_factory.cc
+++ b/src/cli/service/ai/service_factory.cc
@@ -1,5 +1,6 @@
 #include "cli/service/ai/service_factory.h"
 
+#include <cstdlib>
 #include <cstring>
 #include <iostream>
 
@@ -112,6 +113,8 @@ absl::StatusOr<std::unique_ptr<AIService>> CreateAIServiceStrict(
     ollama_config.base_url = config.ollama_host;
     if (!config.model.empty()) {
       ollama_config.model = config.model;
+    } else if (const char* env_model = std::getenv("OLLAMA_MODEL")) {
+      ollama_config.model = env_model;
     }
 
     auto service = std::make_unique<OllamaAIService>(ollama_config);
diff --git a/src/cli/service/ai/service_factory_stub.cc b/src/cli/service/ai/service_factory_stub.cc
new file mode 100644
index 00000000..c1915ea9
--- /dev/null
+++ b/src/cli/service/ai/service_factory_stub.cc
@@ -0,0 +1,27 @@
+#ifndef YAZE_AI_RUNTIME_AVAILABLE
+
+#include "cli/service/ai/service_factory.h"
+
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+
+namespace yaze::cli {
+
+std::unique_ptr<AIService> CreateAIService() {
+  return std::make_unique<MockAIService>();
+}
+
+std::unique_ptr<AIService> CreateAIService(const AIServiceConfig&) {
+  return std::make_unique<MockAIService>();
+}
+
+absl::StatusOr<std::unique_ptr<AIService>> CreateAIServiceStrict(
+    const AIServiceConfig&) {
+  return absl::FailedPreconditionError(
+      "AI runtime features are disabled in this build");
+}
+
+}  // namespace yaze::cli
+
+#endif  // !YAZE_AI_RUNTIME_AVAILABLE
+