feat: arcticfox in the wild

codex-rs/app-server-protocol/src/protocol/common.rs

@@ -528,7 +528,7 @@ mod tests {
         let request = ClientRequest::NewConversation {
             request_id: RequestId::Integer(42),
             params: v1::NewConversationParams {
-                model: Some("arcticfox".to_string()),
+                model: Some("gpt-5.1-codex-max".to_string()),
                 model_provider: None,
                 profile: None,
                 cwd: None,
@@ -546,7 +546,7 @@ mod tests {
                 "method": "newConversation",
                 "id": 42,
                 "params": {
-                    "model": "arcticfox",
+                    "model": "gpt-5.1-codex-max",
                     "modelProvider": null,
                     "profile": null,
                     "cwd": null,

codex-rs/app-server/tests/suite/config.rs

@@ -27,7 +27,7 @@ fn create_config_toml(codex_home: &Path) -> std::io::Result<()> {
     std::fs::write(
         config_toml,
         r#"
-model = "arcticfox"
+model = "gpt-5.1-codex-max"
 approval_policy = "on-request"
 sandbox_mode = "workspace-write"
 model_reasoning_summary = "detailed"
@@ -87,7 +87,7 @@ async fn get_config_toml_parses_all_fields() -> Result<()> {
             }),
             forced_chatgpt_workspace_id: Some("12345678-0000-0000-0000-000000000000".into()),
             forced_login_method: Some(ForcedLoginMethod::Chatgpt),
-            model: Some("arcticfox".into()),
+            model: Some("gpt-5.1-codex-max".into()),
             model_reasoning_effort: Some(ReasoningEffort::High),
             model_reasoning_summary: Some(ReasoningSummary::Detailed),
             model_verbosity: Some(Verbosity::Medium),

codex-rs/app-server/tests/suite/set_default_model.rs

@@ -57,7 +57,7 @@ fn create_config_toml(codex_home: &Path) -> std::io::Result<()> {
     std::fs::write(
         config_toml,
         r#"
-model = "arcticfox"
+model = "gpt-5.1-codex-max"
 model_reasoning_effort = "medium"
 "#,
     )

codex-rs/app-server/tests/suite/v2/model_list.rs

@@ -46,9 +46,9 @@ async fn list_models_returns_all_models_with_large_limit() -> Result<()> {
 
     let expected_models = vec![
         Model {
-            id: "arcticfox".to_string(),
-            model: "arcticfox".to_string(),
-            display_name: "arcticfox".to_string(),
+            id: "gpt-5.1-codex-max".to_string(),
+            model: "gpt-5.1-codex-max".to_string(),
+            display_name: "gpt-5.1-codex-max".to_string(),
             description: "Latest Codex-optimized flagship for deep and fast reasoning.".to_string(),
             supported_reasoning_efforts: vec![
                 ReasoningEffortOption {
@@ -174,7 +174,7 @@ async fn list_models_pagination_works() -> Result<()> {
     } = to_response::<ModelListResponse>(first_response)?;
 
     assert_eq!(first_items.len(), 1);
-    assert_eq!(first_items[0].id, "arcticfox");
+    assert_eq!(first_items[0].id, "gpt-5.1-codex-max");
     let next_cursor = first_cursor.ok_or_else(|| anyhow!("cursor for second page"))?;
 
     let second_request = mcp

codex-rs/app-server/tests/suite/v2/thread_resume.rs

@@ -27,7 +27,7 @@ async fn thread_resume_returns_original_thread() -> Result<()> {
     // Start a thread.
     let start_id = mcp
         .send_thread_start_request(ThreadStartParams {
-            model: Some("arcticfox".to_string()),
+            model: Some("gpt-5.1-codex-max".to_string()),
             ..Default::default()
         })
         .await?;
@@ -69,7 +69,7 @@ async fn thread_resume_prefers_path_over_thread_id() -> Result<()> {
 
     let start_id = mcp
         .send_thread_start_request(ThreadStartParams {
-            model: Some("arcticfox".to_string()),
+            model: Some("gpt-5.1-codex-max".to_string()),
             ..Default::default()
         })
         .await?;
@@ -114,7 +114,7 @@ async fn thread_resume_supports_history_and_overrides() -> Result<()> {
     // Start a thread.
     let start_id = mcp
         .send_thread_start_request(ThreadStartParams {
-            model: Some("arcticfox".to_string()),
+            model: Some("gpt-5.1-codex-max".to_string()),
             ..Default::default()
         })
         .await?;

codex-rs/common/src/model_presets.rs

@@ -5,7 +5,8 @@ use codex_core::protocol_config_types::ReasoningEffort;
 use once_cell::sync::Lazy;
 
 pub const HIDE_GPT5_1_MIGRATION_PROMPT_CONFIG: &str = "hide_gpt5_1_migration_prompt";
-pub const HIDE_ARCTICFOX_MIGRATION_PROMPT_CONFIG: &str = "hide_arcticfox_migration_prompt";
+pub const HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG: &str =
+    "hide_gpt-5.1-codex-max_migration_prompt";
 
 /// A reasoning effort option that can be surfaced for a model.
 #[derive(Debug, Clone, Copy)]
@@ -49,9 +50,9 @@ pub struct ModelPreset {
 static PRESETS: Lazy<Vec<ModelPreset>> = Lazy::new(|| {
     vec![
         ModelPreset {
-            id: "arcticfox",
-            model: "arcticfox",
-            display_name: "arcticfox",
+            id: "gpt-5.1-codex-max",
+            model: "gpt-5.1-codex-max",
+            display_name: "gpt-5.1-codex-max",
             description: "Latest Codex-optimized flagship for deep and fast reasoning.",
             default_reasoning_effort: ReasoningEffort::Medium,
             supported_reasoning_efforts: &[
@@ -98,9 +99,9 @@ static PRESETS: Lazy<Vec<ModelPreset>> = Lazy::new(|| {
             ],
             is_default: false,
             upgrade: Some(ModelUpgrade {
-                id: "arcticfox",
+                id: "gpt-5.1-codex-max",
                 reasoning_effort_mapping: None,
-                migration_config_key: HIDE_ARCTICFOX_MIGRATION_PROMPT_CONFIG,
+                migration_config_key: HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG,
             }),
             show_in_picker: true,
         },
@@ -121,7 +122,11 @@ static PRESETS: Lazy<Vec<ModelPreset>> = Lazy::new(|| {
                 },
             ],
             is_default: false,
-            upgrade: None,
+            upgrade: Some(ModelUpgrade {
+                id: "gpt-5.1-codex-max",
+                reasoning_effort_mapping: None,
+                migration_config_key: HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG,
+            }),
             show_in_picker: true,
         },
         ModelPreset {
@@ -145,7 +150,11 @@ static PRESETS: Lazy<Vec<ModelPreset>> = Lazy::new(|| {
                 },
             ],
             is_default: false,
-            upgrade: None,
+            upgrade: Some(ModelUpgrade {
+                id: "gpt-5.1-codex-max",
+                reasoning_effort_mapping: None,
+                migration_config_key: HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG,
+            }),
             show_in_picker: true,
         },
         // Deprecated models.
@@ -171,9 +180,9 @@ static PRESETS: Lazy<Vec<ModelPreset>> = Lazy::new(|| {
             ],
             is_default: false,
             upgrade: Some(ModelUpgrade {
-                id: "arcticfox",
+                id: "gpt-5.1-codex-max",
                 reasoning_effort_mapping: None,
-                migration_config_key: HIDE_ARCTICFOX_MIGRATION_PROMPT_CONFIG,
+                migration_config_key: HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG,
             }),
             show_in_picker: false,
         },
@@ -227,12 +236,9 @@ static PRESETS: Lazy<Vec<ModelPreset>> = Lazy::new(|| {
             ],
             is_default: false,
             upgrade: Some(ModelUpgrade {
-                id: "gpt-5.1",
-                reasoning_effort_mapping: Some(HashMap::from([(
-                    ReasoningEffort::Minimal,
-                    ReasoningEffort::Low,
-                )])),
-                migration_config_key: HIDE_GPT5_1_MIGRATION_PROMPT_CONFIG,
+                id: "gpt-5.1-codex-max",
+                reasoning_effort_mapping: None,
+                migration_config_key: HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG,
             }),
             show_in_picker: false,
         },
@@ -243,7 +249,7 @@ pub fn builtin_model_presets(auth_mode: Option<AuthMode>) -> Vec<ModelPreset> {
     PRESETS
         .iter()
         .filter(|preset| match auth_mode {
-            Some(AuthMode::ApiKey) => preset.show_in_picker && preset.id != "arcticfox",
+            Some(AuthMode::ApiKey) => preset.show_in_picker && preset.id != "gpt-5.1-codex-max",
             _ => preset.show_in_picker,
         })
         .cloned()
@@ -266,8 +272,12 @@ mod tests {
     }
 
     #[test]
-    fn arcticfox_hidden_for_api_key_auth() {
+    fn gpt_5_1_codex_max_hidden_for_api_key_auth() {
         let presets = builtin_model_presets(Some(AuthMode::ApiKey));
-        assert!(presets.iter().all(|preset| preset.id != "arcticfox"));
+        assert!(
+            presets
+                .iter()
+                .all(|preset| preset.id != "gpt-5.1-codex-max")
+        );
     }
 }

codex-rs/core/src/client_common.rs

@@ -431,7 +431,7 @@ mod tests {
                 expects_apply_patch_instructions: false,
             },
             InstructionsTestCase {
-                slug: "arcticfox",
+                slug: "gpt-5.1-codex-max",
                 expects_apply_patch_instructions: false,
             },
         ];

codex-rs/core/src/config/edit.rs

@@ -846,7 +846,7 @@ hide_gpt5_1_migration_prompt = true
     }
 
     #[test]
-    fn blocking_set_hide_arcticfox_migration_prompt_preserves_table() {
+    fn blocking_set_hide_gpt_5_1_codex_max_migration_prompt_preserves_table() {
         let tmp = tempdir().expect("tmpdir");
         let codex_home = tmp.path();
         std::fs::write(
@@ -860,7 +860,7 @@ existing = "value"
             codex_home,
             None,
             &[ConfigEdit::SetNoticeHideModelMigrationPrompt(
-                "hide_arcticfox_migration_prompt".to_string(),
+                "hide_gpt-5.1-codex-max_migration_prompt".to_string(),
                 true,
             )],
         )
@@ -870,7 +870,7 @@ existing = "value"
             std::fs::read_to_string(codex_home.join(CONFIG_TOML_FILE)).expect("read config");
         let expected = r#"[notice]
 existing = "value"
-hide_arcticfox_migration_prompt = true
+"hide_gpt-5.1-codex-max_migration_prompt" = true
 "#;
         assert_eq!(contents, expected);
     }

codex-rs/core/src/config/mod.rs

@@ -62,11 +62,11 @@ pub mod profile;
 pub mod types;
 
 #[cfg(target_os = "windows")]
-pub const OPENAI_DEFAULT_MODEL: &str = "arcticfox";
+pub const OPENAI_DEFAULT_MODEL: &str = "gpt-5.1-codex-max";
 #[cfg(not(target_os = "windows"))]
-pub const OPENAI_DEFAULT_MODEL: &str = "arcticfox";
-const OPENAI_DEFAULT_REVIEW_MODEL: &str = "arcticfox";
-pub const GPT_5_CODEX_MEDIUM_MODEL: &str = "arcticfox";
+pub const OPENAI_DEFAULT_MODEL: &str = "gpt-5.1-codex-max";
+const OPENAI_DEFAULT_REVIEW_MODEL: &str = "gpt-5.1-codex-max";
+pub const GPT_5_CODEX_MEDIUM_MODEL: &str = "gpt-5.1-codex-max";
 
 /// Maximum number of bytes of the documentation that will be embedded. Larger
 /// files are *silently truncated* to this size so we do not take up too much of
@@ -81,7 +81,7 @@ pub struct Config {
     /// Optional override of model selection.
     pub model: String,
 
-    /// Model used specifically for review sessions. Defaults to "arcticfox".
+    /// Model used specifically for review sessions. Defaults to "gpt-5.1-codex-max".
     pub review_model: String,
 
     pub model_family: ModelFamily,

codex-rs/core/src/config/types.rs

@@ -378,8 +378,8 @@ pub struct Notice {
     pub hide_rate_limit_model_nudge: Option<bool>,
     /// Tracks whether the user has seen the model migration prompt
     pub hide_gpt5_1_migration_prompt: Option<bool>,
-    /// Tracks whether the user has seen the arcticfox migration prompt
-    pub hide_arcticfox_migration_prompt: Option<bool>,
+    /// Tracks whether the user has seen the gpt-5.1-codex-max migration prompt
+    pub hide_gpt_5_1_codex_max_migration_prompt: Option<bool>,
 }
 
 impl Notice {

codex-rs/core/src/model_family.rs

@@ -12,7 +12,7 @@ const BASE_INSTRUCTIONS: &str = include_str!("../prompt.md");
 
 const GPT_5_CODEX_INSTRUCTIONS: &str = include_str!("../gpt_5_codex_prompt.md");
 const GPT_5_1_INSTRUCTIONS: &str = include_str!("../gpt_5_1_prompt.md");
-const ARCTICFOX_INSTRUCTIONS: &str = include_str!("../arcticfox_prompt.md");
+const GPT_5_1_CODEX_MAX_INSTRUCTIONS: &str = include_str!("../gpt-5.1-codex-max_prompt.md");
 
 /// A model family is a group of models that share certain characteristics.
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -173,12 +173,12 @@ pub fn find_family_for_model(slug: &str) -> Option<ModelFamily> {
             support_verbosity: true,
             truncation_policy: TruncationPolicy::Tokens(10_000),
         )
-    } else if slug.starts_with("arcticfox") {
+    } else if slug.starts_with("gpt-5.1-codex-max") {
         model_family!(
             slug, slug,
             supports_reasoning_summaries: true,
             reasoning_summary_format: ReasoningSummaryFormat::Experimental,
-            base_instructions: ARCTICFOX_INSTRUCTIONS.to_string(),
+            base_instructions: GPT_5_1_CODEX_MAX_INSTRUCTIONS.to_string(),
             apply_patch_tool_type: Some(ApplyPatchToolType::Freeform),
             shell_type: ConfigShellToolType::ShellCommand,
             supports_parallel_tool_calls: true,
@@ -202,7 +202,7 @@ pub fn find_family_for_model(slug: &str) -> Option<ModelFamily> {
             support_verbosity: false,
             truncation_policy: TruncationPolicy::Tokens(10_000),
         )
-    } else if slug.starts_with("arcticfox") {
+    } else if slug.starts_with("gpt-5.1-codex-max") {
         model_family!(
             slug, slug,
             supports_reasoning_summaries: true,

codex-rs/core/src/openai_model_info.rs

@@ -72,7 +72,7 @@ pub(crate) fn get_model_info(model_family: &ModelFamily) -> Option<ModelInfo> {
 
         _ if slug.starts_with("gpt-5-codex")
             || slug.starts_with("gpt-5.1-codex")
-            || slug.starts_with("arcticfox") =>
+            || slug.starts_with("gpt-5.1-codex-max") =>
         {
             Some(ModelInfo::new(CONTEXT_WINDOW_272K, MAX_OUTPUT_TOKENS_128K))
         }

codex-rs/core/tests/suite/client.rs

@@ -1155,7 +1155,7 @@ async fn token_count_includes_rate_limits_snapshot() {
                     "reasoning_output_tokens": 0,
                     "total_tokens": 123
                 },
-                // Default model is arcticfox in tests → 95% usable context window
+                // Default model is gpt-5.1-codex-max in tests → 95% usable context window
                 "model_context_window": 258400
             },
             "rate_limits": {