Launch image generation by default (#17153)

## Summary
- Promote `image_generation` from under-development to stable
- Enable image generation by default in the feature registry
- Update feature coverage for the new launch-state expectation
- Add the missing image-generation auth fixture field in a tool registry
test

## Testing
- `just fmt`
- `cargo test -p codex-features`
- `cargo test -p codex-tools` currently fails:
`test_full_toolset_specs_for_gpt5_codex_unified_exec_web_search` needs
its expected default tool list updated for `image_generation`

codex-rs/core/src/tools/spec_tests.rs

@@ -417,6 +417,7 @@ async fn test_build_specs_gpt5_codex_default() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -441,6 +442,7 @@ async fn test_build_specs_gpt51_codex_default() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -467,6 +469,7 @@ async fn test_build_specs_gpt5_codex_unified_exec_web_search() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -493,6 +496,7 @@ async fn test_build_specs_gpt51_codex_unified_exec_web_search() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -517,6 +521,7 @@ async fn test_gpt_5_1_codex_max_defaults() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -541,6 +546,7 @@ async fn test_codex_5_1_mini_defaults() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -564,6 +570,7 @@ async fn test_gpt_5_defaults() {
             "update_plan",
             "request_user_input",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -588,6 +595,7 @@ async fn test_gpt_5_1_defaults() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",
@@ -614,6 +622,7 @@ async fn test_gpt_5_1_codex_max_unified_exec_web_search() {
             "request_user_input",
             "apply_patch",
             "web_search",
+            "image_generation",
             "view_image",
             "spawn_agent",
             "send_input",

codex-rs/features/src/lib.rs

@@ -812,8 +812,8 @@ pub const FEATURES: &[FeatureSpec] = &[
     FeatureSpec {
         id: Feature::ImageGeneration,
         key: "image_generation",
-        stage: Stage::UnderDevelopment,
-        default_enabled: false,
+        stage: Stage::Stable,
+        default_enabled: true,
     },
     FeatureSpec {
         id: Feature::SkillMcpDependencyInstall,

codex-rs/features/src/tests.rs

@@ -160,6 +160,12 @@ fn use_linux_sandbox_bwrap_is_a_removed_feature_key() {
     );
 }
 
+#[test]
+fn image_generation_is_stable_and_enabled_by_default() {
+    assert_eq!(Feature::ImageGeneration.stage(), Stage::Stable);
+    assert_eq!(Feature::ImageGeneration.default_enabled(), true);
+}
+
 #[test]
 fn image_detail_original_is_a_removed_feature_key() {
     assert_eq!(
@@ -168,12 +174,6 @@ fn image_detail_original_is_a_removed_feature_key() {
     );
 }
 
-#[test]
-fn image_generation_is_under_development() {
-    assert_eq!(Feature::ImageGeneration.stage(), Stage::UnderDevelopment);
-    assert_eq!(Feature::ImageGeneration.default_enabled(), false);
-}
-
 #[test]
 fn tool_call_mcp_elicitation_is_stable_and_enabled_by_default() {
     assert_eq!(Feature::ToolCallMcpElicitation.stage(), Stage::Stable);

codex-rs/tools/src/tool_registry_plan_tests.rs

@@ -97,6 +97,7 @@ fn test_full_toolset_specs_for_gpt5_codex_unified_exec_web_search() {
             search_context_size: None,
             search_content_types: None,
         },
+        create_image_generation_tool("png"),
         create_view_image_tool(ViewImageToolOptions {
             can_request_original_image_detail: config.can_request_original_image_detail,
         }),