feat: update default (#4076)

Changes:
- Default model and docs now use gpt-5-codex. 
- Disables the GPT-5 Codex NUX by default.
- Keeps presets available for API key users.

Author: tibo-openai

codex-rs/common/src/model_presets.rs

@@ -1,4 +1,3 @@
-use codex_core::config::GPT_5_CODEX_MEDIUM_MODEL;
 use codex_core::protocol_config_types::ReasoningEffort;
 use codex_protocol::mcp_protocol::AuthMode;
 
@@ -69,13 +68,6 @@ const PRESETS: &[ModelPreset] = &[
     },
 ];
 
-pub fn builtin_model_presets(auth_mode: Option<AuthMode>) -> Vec<ModelPreset> {
-    match auth_mode {
-        Some(AuthMode::ApiKey) => PRESETS
-            .iter()
-            .copied()
-            .filter(|p| p.model != GPT_5_CODEX_MEDIUM_MODEL)
-            .collect(),
-        _ => PRESETS.to_vec(),
-    }
+pub fn builtin_model_presets(_auth_mode: Option<AuthMode>) -> Vec<ModelPreset> {
+    PRESETS.to_vec()
 }

codex-rs/core/src/config.rs

@@ -37,7 +37,7 @@ use toml_edit::DocumentMut;
 use toml_edit::Item as TomlItem;
 use toml_edit::Table as TomlTable;
 
-const OPENAI_DEFAULT_MODEL: &str = "gpt-5";
+const OPENAI_DEFAULT_MODEL: &str = "gpt-5-codex";
 const OPENAI_DEFAULT_REVIEW_MODEL: &str = "gpt-5-codex";
 pub const GPT_5_CODEX_MEDIUM_MODEL: &str = "gpt-5-codex";
 
@@ -54,7 +54,7 @@ pub struct Config {
     /// Optional override of model selection.
     pub model: String,
 
-    /// Model used specifically for review sessions. Defaults to "gpt-5".
+    /// Model used specifically for review sessions. Defaults to "gpt-5-codex".
     pub review_model: String,
 
     pub model_family: ModelFamily,
@@ -1366,7 +1366,7 @@ startup_timeout_ms = 2500
         tokio::fs::write(
             &config_path,
             r#"
-model = "gpt-5"
+model = "gpt-5-codex"
 model_reasoning_effort = "medium"
 
 [profiles.dev]
@@ -1441,7 +1441,7 @@ model = "gpt-4"
 model_reasoning_effort = "medium"
 
 [profiles.prod]
-model = "gpt-5"
+model = "gpt-5-codex"
 "#,
         )
         .await?;
@@ -1472,7 +1472,7 @@ model = "gpt-5"
                 .profiles
                 .get("prod")
                 .and_then(|profile| profile.model.as_deref()),
-            Some("gpt-5"),
+            Some("gpt-5-codex"),
         );
 
         Ok(())

codex-rs/core/src/config_edit.rs

@@ -228,15 +228,15 @@ mod tests {
             codex_home,
             None,
             &[
-                (&[CONFIG_KEY_MODEL], "gpt-5"),
+                (&[CONFIG_KEY_MODEL], "gpt-5-codex"),
                 (&[CONFIG_KEY_EFFORT], "high"),
             ],
         )
         .await
         .expect("persist");
 
         let contents = read_config(codex_home).await;
-        let expected = r#"model = "gpt-5"
+        let expected = r#"model = "gpt-5-codex"
 model_reasoning_effort = "high"
 "#;
         assert_eq!(contents, expected);
@@ -348,7 +348,7 @@ model_reasoning_effort = "high"
             &[
                 (&["a", "b", "c"], "v"),
                 (&["x"], "y"),
-                (&["profiles", "p1", CONFIG_KEY_MODEL], "gpt-5"),
+                (&["profiles", "p1", CONFIG_KEY_MODEL], "gpt-5-codex"),
             ],
         )
         .await
@@ -361,7 +361,7 @@ model_reasoning_effort = "high"
 c = "v"
 
 [profiles.p1]
-model = "gpt-5"
+model = "gpt-5-codex"
 "#;
         assert_eq!(contents, expected);
     }
@@ -454,7 +454,7 @@ existing = "keep"
             codex_home,
             None,
             &[
-                (&[CONFIG_KEY_MODEL], "gpt-5"),
+                (&[CONFIG_KEY_MODEL], "gpt-5-codex"),
                 (&[CONFIG_KEY_EFFORT], "minimal"),
             ],
         )
@@ -466,7 +466,7 @@ existing = "keep"
 # should be preserved
 
 existing = "keep"
-model = "gpt-5"
+model = "gpt-5-codex"
 model_reasoning_effort = "minimal"
 "#;
         assert_eq!(contents, expected);
@@ -524,7 +524,7 @@ model = "o3"
         let codex_home = tmpdir.path();
 
         // Seed with a model value only
-        let seed = "model = \"gpt-5\"\n";
+        let seed = "model = \"gpt-5-codex\"\n";
         tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
             .await
             .expect("seed write");
@@ -535,7 +535,7 @@ model = "o3"
             .expect("persist");
 
         let contents = read_config(codex_home).await;
-        let expected = r#"model = "gpt-5"
+        let expected = r#"model = "gpt-5-codex"
 model_reasoning_effort = "high"
 "#;
         assert_eq!(contents, expected);
@@ -579,7 +579,7 @@ model = "o4-mini"
 
         // No active profile key; we'll target an explicit override
         let seed = r#"[profiles.team]
-model = "gpt-5"
+model = "gpt-5-codex"
 "#;
         tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
             .await
@@ -595,7 +595,7 @@ model = "gpt-5"
 
         let contents = read_config(codex_home).await;
         let expected = r#"[profiles.team]
-model = "gpt-5"
+model = "gpt-5-codex"
 model_reasoning_effort = "minimal"
 "#;
         assert_eq!(contents, expected);
@@ -611,15 +611,15 @@ model_reasoning_effort = "minimal"
             codex_home,
             None,
             &[
-                (&[CONFIG_KEY_MODEL], Some("gpt-5")),
+                (&[CONFIG_KEY_MODEL], Some("gpt-5-codex")),
                 (&[CONFIG_KEY_EFFORT], None),
             ],
         )
         .await
         .expect("persist");
 
         let contents = read_config(codex_home).await;
-        let expected = "model = \"gpt-5\"\n";
+        let expected = "model = \"gpt-5-codex\"\n";
         assert_eq!(contents, expected);
     }
 
@@ -670,7 +670,7 @@ model = "o3"
         let tmpdir = tempdir().expect("tmp");
         let codex_home = tmpdir.path();
 
-        let seed = r#"model = "gpt-5"
+        let seed = r#"model = "gpt-5-codex"
 model_reasoning_effort = "medium"
 "#;
         tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)

codex-rs/core/src/internal_storage.rs

@@ -7,14 +7,27 @@ use std::path::PathBuf;
 
 pub(crate) const INTERNAL_STORAGE_FILE: &str = "internal_storage.json";
 
-#[derive(Debug, Default, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct InternalStorage {
     #[serde(skip)]
     storage_path: PathBuf,
-    #[serde(default)]
+    #[serde(default = "default_gpt_5_codex_model_prompt_seen")]
     pub gpt_5_codex_model_prompt_seen: bool,
 }
 
+const fn default_gpt_5_codex_model_prompt_seen() -> bool {
+    true
+}
+
+impl Default for InternalStorage {
+    fn default() -> Self {
+        Self {
+            storage_path: PathBuf::new(),
+            gpt_5_codex_model_prompt_seen: default_gpt_5_codex_model_prompt_seen(),
+        }
+    }
+}
+
 // TODO(jif) generalise all the file writers and build proper async channel inserters.
 impl InternalStorage {
     pub fn load(codex_home: &Path) -> Self {

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

@@ -822,7 +822,7 @@ async fn token_count_includes_rate_limits_snapshot() {
                     "reasoning_output_tokens": 0,
                     "total_tokens": 123
                 },
-                // Default model is gpt-5 in tests → 272000 context window
+                // Default model is gpt-5-codex in tests → 272000 context window
                 "model_context_window": 272000
             },
             "rate_limits": {

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

@@ -133,7 +133,7 @@ async fn compact_resume_and_fork_preserve_model_history_view() {
         .to_string();
     let user_turn_1 = json!(
     {
-      "model": "gpt-5",
+      "model": "gpt-5-codex",
       "instructions": prompt,
       "input": [
         {
@@ -182,7 +182,7 @@ async fn compact_resume_and_fork_preserve_model_history_view() {
     });
     let compact_1 = json!(
     {
-      "model": "gpt-5",
+      "model": "gpt-5-codex",
       "instructions": "You have exceeded the maximum number of tokens, please stop coding and instead write a short memento message for the next agent. Your note should:
 - Summarize what you finished and what still needs work. If there was a recent update_plan call, repeat its steps verbatim.
 - List outstanding TODOs with file paths / line numbers so they're easy to find.
@@ -255,7 +255,7 @@ async fn compact_resume_and_fork_preserve_model_history_view() {
     });
     let user_turn_2_after_compact = json!(
     {
-      "model": "gpt-5",
+      "model": "gpt-5-codex",
       "instructions": prompt,
       "input": [
         {
@@ -320,7 +320,7 @@ SUMMARY_ONLY_CONTEXT"
     });
     let usert_turn_3_after_resume = json!(
     {
-      "model": "gpt-5",
+      "model": "gpt-5-codex",
       "instructions": prompt,
       "input": [
         {
@@ -405,7 +405,7 @@ SUMMARY_ONLY_CONTEXT"
     });
     let user_turn_3_after_fork = json!(
     {
-      "model": "gpt-5",
+      "model": "gpt-5-codex",
       "instructions": prompt,
       "input": [
         {

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

@@ -184,6 +184,7 @@ async fn prompt_tools_are_consistent_across_requests() {
 
     let conversation_manager =
         ConversationManager::with_auth(CodexAuth::from_api_key("Test API Key"));
+    let expected_instructions = config.model_family.base_instructions.clone();
     let codex = conversation_manager
         .new_conversation(config)
         .await
@@ -213,7 +214,6 @@ async fn prompt_tools_are_consistent_across_requests() {
     let requests = server.received_requests().await.unwrap();
     assert_eq!(requests.len(), 2, "expected two POST requests");
 
-    let expected_instructions: &str = include_str!("../../prompt.md");
     // our internal implementation is responsible for keeping tools in sync
     // with the OpenAI schema, so we just verify the tool presence here
     let expected_tools_names: &[&str] = &["shell", "update_plan", "apply_patch", "view_image"];

codex-rs/docs/codex_mcp_interface.md

@@ -51,7 +51,7 @@ Start a new session with optional overrides:
 
 Request `newConversation` params (subset):
 
-- `model`: string model id (e.g. "o3", "gpt-5")
+- `model`: string model id (e.g. "o3", "gpt-5", "gpt-5-codex")
 - `profile`: optional named profile
 - `cwd`: optional working directory
 - `approvalPolicy`: `untrusted` | `on-request` | `on-failure` | `never`
@@ -120,4 +120,3 @@ While processing, the server emits `codex/event` notifications containing agent
 ## Compatibility and stability
 
 This interface is experimental. Method names, fields, and event shapes may evolve. For the authoritative schema, consult `protocol/src/mcp_protocol.rs` and the corresponding server wiring in `mcp-server/`.
-

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

@@ -26,7 +26,7 @@ fn create_config_toml(codex_home: &Path) -> std::io::Result<()> {
     std::fs::write(
         config_toml,
         r#"
-model = "gpt-5"
+model = "gpt-5-codex"
 approval_policy = "on-request"
 sandbox_mode = "workspace-write"
 model_reasoning_summary = "detailed"
@@ -92,7 +92,7 @@ async fn get_config_toml_parses_all_fields() {
                 exclude_tmpdir_env_var: Some(true),
                 exclude_slash_tmp: Some(true),
             }),
-            model: Some("gpt-5".into()),
+            model: Some("gpt-5-codex".into()),
             model_reasoning_effort: Some(ReasoningEffort::High),
             model_reasoning_summary: Some(ReasoningSummary::Detailed),
             model_verbosity: Some(Verbosity::Medium),

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

@@ -69,7 +69,7 @@ fn create_config_toml(codex_home: &Path) -> std::io::Result<()> {
     std::fs::write(
         config_toml,
         r#"
-model = "gpt-5"
+model = "gpt-5-codex"
 model_reasoning_effort = "medium"
 "#,
     )