diff --git a/codex-rs/app-server-protocol/schema/json/ClientRequest.json b/codex-rs/app-server-protocol/schema/json/ClientRequest.json
index ac25bc7822..9ac17b8a03 100644
--- a/codex-rs/app-server-protocol/schema/json/ClientRequest.json
+++ b/codex-rs/app-server-protocol/schema/json/ClientRequest.json
@@ -535,7 +535,7 @@
           ]
         },
         "reloadUserConfig": {
-          "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and personality defaults are not reloaded.",
+          "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier defaults are not reloaded. The deprecated personality setting is also not reloaded.",
           "type": "boolean"
         }
       },
@@ -2335,6 +2335,7 @@
       "type": "object"
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -4941,7 +4942,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
         },
         "sandbox": {
           "anyOf": [
@@ -5267,7 +5269,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated `friendly` and `pragmatic` no longer select a style."
         },
         "sandbox": {
           "anyOf": [
@@ -5541,7 +5544,7 @@
               "type": "null"
             }
           ],
-          "description": "Override the personality for this turn and subsequent turns."
+          "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
         },
         "sandboxPolicy": {
           "anyOf": [
diff --git a/codex-rs/app-server-protocol/schema/json/ServerNotification.json b/codex-rs/app-server-protocol/schema/json/ServerNotification.json
index 1bbe08dcd5..70eb9c821c 100644
--- a/codex-rs/app-server-protocol/schema/json/ServerNotification.json
+++ b/codex-rs/app-server-protocol/schema/json/ServerNotification.json
@@ -3250,6 +3250,7 @@
       ]
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -5983,7 +5984,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style."
         },
         "sandboxPolicy": {
           "$ref": "#/definitions/SandboxPolicy"
diff --git a/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json b/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json
index d16493b10f..209db995b3 100644
--- a/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json
+++ b/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json
@@ -9463,7 +9463,7 @@
             ]
           },
           "reloadUserConfig": {
-            "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and personality defaults are not reloaded.",
+            "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier defaults are not reloaded. The deprecated personality setting is also not reloaded.",
             "type": "boolean"
           }
         },
@@ -15256,6 +15256,7 @@
           },
           "supportsPersonality": {
             "default": false,
+            "description": "@deprecated Always false; models no longer support personality selection.",
             "type": "boolean"
           },
           "upgrade": {
@@ -15969,6 +15970,7 @@
         "type": "object"
       },
       "Personality": {
+        "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
         "enum": [
           "none",
           "friendly",
@@ -23389,7 +23391,8 @@
               {
                 "type": "null"
               }
-            ]
+            ],
+            "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
           },
           "sandbox": {
             "anyOf": [
@@ -23925,7 +23928,8 @@
               {
                 "type": "null"
               }
-            ]
+            ],
+            "description": "@deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style."
           },
           "sandboxPolicy": {
             "$ref": "#/definitions/v2/SandboxPolicy"
@@ -24108,7 +24112,8 @@
               {
                 "type": "null"
               }
-            ]
+            ],
+            "description": "@deprecated `friendly` and `pragmatic` no longer select a style."
           },
           "sandbox": {
             "anyOf": [
@@ -25258,7 +25263,7 @@
                 "type": "null"
               }
             ],
-            "description": "Override the personality for this turn and subsequent turns."
+            "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
           },
           "sandboxPolicy": {
             "anyOf": [
diff --git a/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json b/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json
index 7e41e242d6..56226be9c7 100644
--- a/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json
+++ b/codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json
@@ -5343,7 +5343,7 @@
           ]
         },
         "reloadUserConfig": {
-          "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and personality defaults are not reloaded.",
+          "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier defaults are not reloaded. The deprecated personality setting is also not reloaded.",
           "type": "boolean"
         }
       },
@@ -11308,6 +11308,7 @@
         },
         "supportsPersonality": {
           "default": false,
+          "description": "@deprecated Always false; models no longer support personality selection.",
           "type": "boolean"
         },
         "upgrade": {
@@ -12021,6 +12022,7 @@
       "type": "object"
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -21103,7 +21105,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
         },
         "sandbox": {
           "anyOf": [
@@ -21639,7 +21642,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style."
         },
         "sandboxPolicy": {
           "$ref": "#/definitions/SandboxPolicy"
@@ -21822,7 +21826,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated `friendly` and `pragmatic` no longer select a style."
         },
         "sandbox": {
           "anyOf": [
@@ -22972,7 +22977,7 @@
               "type": "null"
             }
           ],
-          "description": "Override the personality for this turn and subsequent turns."
+          "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
         },
         "sandboxPolicy": {
           "anyOf": [
diff --git a/codex-rs/app-server-protocol/schema/json/v2/ConfigBatchWriteParams.json b/codex-rs/app-server-protocol/schema/json/v2/ConfigBatchWriteParams.json
index e85803e4ea..6d45995ec9 100644
--- a/codex-rs/app-server-protocol/schema/json/v2/ConfigBatchWriteParams.json
+++ b/codex-rs/app-server-protocol/schema/json/v2/ConfigBatchWriteParams.json
@@ -47,7 +47,7 @@
       ]
     },
     "reloadUserConfig": {
-      "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and personality defaults are not reloaded.",
+      "description": "When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier defaults are not reloaded. The deprecated personality setting is also not reloaded.",
       "type": "boolean"
     }
   },
diff --git a/codex-rs/app-server-protocol/schema/json/v2/ModelListResponse.json b/codex-rs/app-server-protocol/schema/json/v2/ModelListResponse.json
index 3868cb9341..8169ec1e8d 100644
--- a/codex-rs/app-server-protocol/schema/json/v2/ModelListResponse.json
+++ b/codex-rs/app-server-protocol/schema/json/v2/ModelListResponse.json
@@ -140,6 +140,7 @@
         },
         "supportsPersonality": {
           "default": false,
+          "description": "@deprecated Always false; models no longer support personality selection.",
           "type": "boolean"
         },
         "upgrade": {
diff --git a/codex-rs/app-server-protocol/schema/json/v2/ThreadResumeParams.json b/codex-rs/app-server-protocol/schema/json/v2/ThreadResumeParams.json
index 2d8a10968f..15f5fa0638 100644
--- a/codex-rs/app-server-protocol/schema/json/v2/ThreadResumeParams.json
+++ b/codex-rs/app-server-protocol/schema/json/v2/ThreadResumeParams.json
@@ -470,6 +470,7 @@
       ]
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -1545,7 +1546,8 @@
         {
           "type": "null"
         }
-      ]
+      ],
+      "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
     },
     "sandbox": {
       "anyOf": [
diff --git a/codex-rs/app-server-protocol/schema/json/v2/ThreadSettingsUpdatedNotification.json b/codex-rs/app-server-protocol/schema/json/v2/ThreadSettingsUpdatedNotification.json
index a1809df664..df128d115e 100644
--- a/codex-rs/app-server-protocol/schema/json/v2/ThreadSettingsUpdatedNotification.json
+++ b/codex-rs/app-server-protocol/schema/json/v2/ThreadSettingsUpdatedNotification.json
@@ -140,6 +140,7 @@
       "type": "string"
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -355,7 +356,8 @@
             {
               "type": "null"
             }
-          ]
+          ],
+          "description": "@deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style."
         },
         "sandboxPolicy": {
           "$ref": "#/definitions/SandboxPolicy"
diff --git a/codex-rs/app-server-protocol/schema/json/v2/ThreadStartParams.json b/codex-rs/app-server-protocol/schema/json/v2/ThreadStartParams.json
index 8bf5ae8bef..5164caf6a2 100644
--- a/codex-rs/app-server-protocol/schema/json/v2/ThreadStartParams.json
+++ b/codex-rs/app-server-protocol/schema/json/v2/ThreadStartParams.json
@@ -220,6 +220,7 @@
       ]
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -373,7 +374,8 @@
         {
           "type": "null"
         }
-      ]
+      ],
+      "description": "@deprecated `friendly` and `pragmatic` no longer select a style."
     },
     "sandbox": {
       "anyOf": [
diff --git a/codex-rs/app-server-protocol/schema/json/v2/TurnStartParams.json b/codex-rs/app-server-protocol/schema/json/v2/TurnStartParams.json
index 5b9105d8e9..c0cb6dfd4a 100644
--- a/codex-rs/app-server-protocol/schema/json/v2/TurnStartParams.json
+++ b/codex-rs/app-server-protocol/schema/json/v2/TurnStartParams.json
@@ -312,6 +312,7 @@
       "type": "string"
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -827,7 +828,7 @@
           "type": "null"
         }
       ],
-      "description": "Override the personality for this turn and subsequent turns."
+      "description": "@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
     },
     "sandboxPolicy": {
       "anyOf": [
diff --git a/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-experimental.json.zst b/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-experimental.json.zst
index e0c3d9b552..179d1b46b9 100644
Binary files a/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-experimental.json.zst and b/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-experimental.json.zst differ
diff --git a/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-stable.json.zst b/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-stable.json.zst
index c9d2d872aa..d93732d82c 100644
Binary files a/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-stable.json.zst and b/codex-rs/app-server-protocol/schema/precomputed/app-server-exports-stable.json.zst differ
diff --git a/codex-rs/app-server-protocol/schema/typescript/Personality.ts b/codex-rs/app-server-protocol/schema/typescript/Personality.ts
index 45165f4e33..a2179fc2a6 100644
--- a/codex-rs/app-server-protocol/schema/typescript/Personality.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/Personality.ts
@@ -2,4 +2,7 @@
 
 // This file was generated by [ts-rs](https://github.com/Aleph-Alpha/ts-rs). Do not edit this file manually.
 
+/**
+ * Deprecated: `friendly` and `pragmatic` no longer select a style.
+ */
 export type Personality = "none" | "friendly" | "pragmatic";
diff --git a/codex-rs/app-server-protocol/schema/typescript/v2/ConfigBatchWriteParams.ts b/codex-rs/app-server-protocol/schema/typescript/v2/ConfigBatchWriteParams.ts
index fe82988a21..2340941944 100644
--- a/codex-rs/app-server-protocol/schema/typescript/v2/ConfigBatchWriteParams.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/v2/ConfigBatchWriteParams.ts
@@ -10,7 +10,7 @@ export type ConfigBatchWriteParams = { edits: Array<ConfigEdit>,
 filePath?: string | null, expectedVersion?: string | null,
 /**
  * When true, hot-reload updated runtime settings into loaded threads after writing.
- * Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and
- * personality defaults are not reloaded.
+ * Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier
+ * defaults are not reloaded. The deprecated personality setting is also not reloaded.
  */
 reloadUserConfig?: boolean, };
diff --git a/codex-rs/app-server-protocol/schema/typescript/v2/Model.ts b/codex-rs/app-server-protocol/schema/typescript/v2/Model.ts
index 9508b3480c..6a1c065eeb 100644
--- a/codex-rs/app-server-protocol/schema/typescript/v2/Model.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/v2/Model.ts
@@ -10,7 +10,11 @@ import type { ModelUpgradeInfo } from "./ModelUpgradeInfo";
 import type { MultiAgentVersion } from "./MultiAgentVersion";
 import type { ReasoningEffortOption } from "./ReasoningEffortOption";
 
-export type Model = { id: string, model: string, upgrade: string | null, upgradeInfo: ModelUpgradeInfo | null, availabilityNux: ModelAvailabilityNux | null, displayName: string, description: string, modelSpecialty: string | null, hidden: boolean, supportedReasoningEfforts: Array<ReasoningEffortOption>, defaultReasoningEffort: ReasoningEffort, inputModalities: Array<InputModality>, supportsPersonality: boolean,
+export type Model = { id: string, model: string, upgrade: string | null, upgradeInfo: ModelUpgradeInfo | null, availabilityNux: ModelAvailabilityNux | null, displayName: string, description: string, modelSpecialty: string | null, hidden: boolean, supportedReasoningEfforts: Array<ReasoningEffortOption>, defaultReasoningEffort: ReasoningEffort, inputModalities: Array<InputModality>,
+/**
+ * @deprecated Always false; models no longer support personality selection.
+ */
+supportsPersonality: boolean,
 /**
  * Multi-agent runtime declared by this model, when available.
  */
diff --git a/codex-rs/app-server-protocol/schema/typescript/v2/ThreadResumeParams.ts b/codex-rs/app-server-protocol/schema/typescript/v2/ThreadResumeParams.ts
index d9918d91ea..4da03970e9 100644
--- a/codex-rs/app-server-protocol/schema/typescript/v2/ThreadResumeParams.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/v2/ThreadResumeParams.ts
@@ -30,7 +30,11 @@ model?: string | null, modelProvider?: string | null, serviceTier?: string | nul
  * Override where approval requests are routed for review on this thread
  * and subsequent turns.
  */
-approvalsReviewer?: ApprovalsReviewer | null, sandbox?: SandboxMode | null, config?: { [key in string]?: JsonValue } | null, baseInstructions?: string | null, developerInstructions?: string | null, personality?: Personality | null, /**
+approvalsReviewer?: ApprovalsReviewer | null, sandbox?: SandboxMode | null, config?: { [key in string]?: JsonValue } | null, baseInstructions?: string | null, developerInstructions?: string | null, /**
+ * @deprecated `friendly` and `pragmatic` no longer select a style.
+ * Changing this does not rewrite the thread's existing instructions.
+ */
+personality?: Personality | null, /**
  * When true, return only thread metadata and live-resume state without
  * populating `thread.turns`. This is useful when the client plans to call
  * `thread/turns/list` immediately after resuming. Full-history hydration
diff --git a/codex-rs/app-server-protocol/schema/typescript/v2/ThreadSettings.ts b/codex-rs/app-server-protocol/schema/typescript/v2/ThreadSettings.ts
index 71b566b99b..90818f634e 100644
--- a/codex-rs/app-server-protocol/schema/typescript/v2/ThreadSettings.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/v2/ThreadSettings.ts
@@ -14,4 +14,7 @@ import type { SandboxPolicy } from "./SandboxPolicy";
 export type ThreadSettings = {/**
  * Saved list of disabled plugin IDs. Does not yet filter plugin capabilities.
  */
-disabledPluginIds: Array<string>, cwd: AbsolutePathBuf, approvalPolicy: AskForApproval, approvalsReviewer: ApprovalsReviewer, sandboxPolicy: SandboxPolicy, activePermissionProfile: ActivePermissionProfile | null, model: string, modelProvider: string, serviceTier: string | null, effort: ReasoningEffort | null, summary: ReasoningSummary | null, collaborationMode: CollaborationMode, personality: Personality | null};
+disabledPluginIds: Array<string>, cwd: AbsolutePathBuf, approvalPolicy: AskForApproval, approvalsReviewer: ApprovalsReviewer, sandboxPolicy: SandboxPolicy, activePermissionProfile: ActivePermissionProfile | null, model: string, modelProvider: string, serviceTier: string | null, effort: ReasoningEffort | null, summary: ReasoningSummary | null, collaborationMode: CollaborationMode, /**
+ * @deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style.
+ */
+personality: Personality | null};
diff --git a/codex-rs/app-server-protocol/schema/typescript/v2/ThreadStartParams.ts b/codex-rs/app-server-protocol/schema/typescript/v2/ThreadStartParams.ts
index 30509ef6cb..69280c0b38 100644
--- a/codex-rs/app-server-protocol/schema/typescript/v2/ThreadStartParams.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/v2/ThreadStartParams.ts
@@ -13,7 +13,10 @@ export type ThreadStartParams = {model?: string | null, modelProvider?: string |
  * Override where approval requests are routed for review on this thread
  * and subsequent turns.
  */
-approvalsReviewer?: ApprovalsReviewer | null, sandbox?: SandboxMode | null, config?: { [key in string]?: JsonValue } | null, serviceName?: string | null, baseInstructions?: string | null, developerInstructions?: string | null, personality?: Personality | null, ephemeral?: boolean | null, sessionStartSource?: ThreadStartSource | null, /**
+approvalsReviewer?: ApprovalsReviewer | null, sandbox?: SandboxMode | null, config?: { [key in string]?: JsonValue } | null, serviceName?: string | null, baseInstructions?: string | null, developerInstructions?: string | null, /**
+ * @deprecated `friendly` and `pragmatic` no longer select a style.
+ */
+personality?: Personality | null, ephemeral?: boolean | null, sessionStartSource?: ThreadStartSource | null, /**
  * Optional client-supplied analytics source classification for this thread.
  */
 threadSource?: ThreadSource | null};
diff --git a/codex-rs/app-server-protocol/schema/typescript/v2/TurnStartParams.ts b/codex-rs/app-server-protocol/schema/typescript/v2/TurnStartParams.ts
index b201450e73..b5f5321916 100644
--- a/codex-rs/app-server-protocol/schema/typescript/v2/TurnStartParams.ts
+++ b/codex-rs/app-server-protocol/schema/typescript/v2/TurnStartParams.ts
@@ -50,7 +50,8 @@ effort?: ReasoningEffort | null, /**
  * Override the reasoning summary for this turn and subsequent turns.
  */
 summary?: ReasoningSummary | null, /**
- * Override the personality for this turn and subsequent turns.
+ * @deprecated `friendly` and `pragmatic` no longer select a style.
+ * Changing this does not rewrite the thread's existing instructions.
  */
 personality?: Personality | null, /**
  * Optional JSON Schema used to constrain the final assistant message for
diff --git a/codex-rs/app-server-protocol/src/protocol/v2/config.rs b/codex-rs/app-server-protocol/src/protocol/v2/config.rs
index 54c6c91cd3..cda88a7432 100644
--- a/codex-rs/app-server-protocol/src/protocol/v2/config.rs
+++ b/codex-rs/app-server-protocol/src/protocol/v2/config.rs
@@ -1089,8 +1089,8 @@ pub struct ConfigBatchWriteParams {
     #[ts(optional = nullable)]
     pub expected_version: Option<String>,
     /// When true, hot-reload updated runtime settings into loaded threads after writing.
-    /// Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and
-    /// personality defaults are not reloaded.
+    /// Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier
+    /// defaults are not reloaded. The deprecated personality setting is also not reloaded.
     #[serde(default, skip_serializing_if = "std::ops::Not::not")]
     pub reload_user_config: bool,
 }
diff --git a/codex-rs/app-server-protocol/src/protocol/v2/model.rs b/codex-rs/app-server-protocol/src/protocol/v2/model.rs
index 0bf6de04e0..b6311ffd7a 100644
--- a/codex-rs/app-server-protocol/src/protocol/v2/model.rs
+++ b/codex-rs/app-server-protocol/src/protocol/v2/model.rs
@@ -131,6 +131,7 @@ pub struct Model {
     pub default_reasoning_effort: ReasoningEffort,
     #[serde(default = "default_input_modalities")]
     pub input_modalities: Vec<InputModality>,
+    /// @deprecated Always false; models no longer support personality selection.
     #[serde(default)]
     pub supports_personality: bool,
     /// Multi-agent runtime declared by this model, when available.
diff --git a/codex-rs/app-server-protocol/src/protocol/v2/thread.rs b/codex-rs/app-server-protocol/src/protocol/v2/thread.rs
index 162adb13bb..09732cfb43 100644
--- a/codex-rs/app-server-protocol/src/protocol/v2/thread.rs
+++ b/codex-rs/app-server-protocol/src/protocol/v2/thread.rs
@@ -104,6 +104,7 @@ pub struct ThreadStartParams {
     pub base_instructions: Option<String>,
     #[ts(optional = nullable)]
     pub developer_instructions: Option<String>,
+    /// @deprecated `friendly` and `pragmatic` no longer select a style.
     #[ts(optional = nullable)]
     pub personality: Option<Personality>,
     /// @deprecated Ignored. Use Ultra reasoning effort for proactive multi-agent behavior.
@@ -286,7 +287,8 @@ pub struct ThreadSettingsUpdateParams {
     #[experimental("thread/settings/update.multiAgentMode")]
     #[ts(optional = nullable)]
     pub multi_agent_mode: Option<MultiAgentMode>,
-    /// Override the personality for subsequent turns.
+    /// @deprecated `friendly` and `pragmatic` no longer select a style.
+    /// Changing this does not rewrite the thread's existing instructions.
     #[ts(optional = nullable)]
     pub personality: Option<Personality>,
 }
@@ -318,6 +320,7 @@ pub struct ThreadSettings {
     #[experimental("thread/settings.multiAgentMode")]
     #[serde(default)]
     pub multi_agent_mode: MultiAgentMode,
+    /// @deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style.
     pub personality: Option<Personality>,
 }
 
@@ -409,6 +412,8 @@ pub struct ThreadResumeParams {
     pub base_instructions: Option<String>,
     #[ts(optional = nullable)]
     pub developer_instructions: Option<String>,
+    /// @deprecated `friendly` and `pragmatic` no longer select a style.
+    /// Changing this does not rewrite the thread's existing instructions.
     #[ts(optional = nullable)]
     pub personality: Option<Personality>,
     /// When true, return only thread metadata and live-resume state without
diff --git a/codex-rs/app-server-protocol/src/protocol/v2/turn.rs b/codex-rs/app-server-protocol/src/protocol/v2/turn.rs
index 3435ae6402..f938d179e6 100644
--- a/codex-rs/app-server-protocol/src/protocol/v2/turn.rs
+++ b/codex-rs/app-server-protocol/src/protocol/v2/turn.rs
@@ -248,7 +248,8 @@ pub struct TurnStartParams {
     /// Override the reasoning summary for this turn and subsequent turns.
     #[ts(optional = nullable)]
     pub summary: Option<ReasoningSummary>,
-    /// Override the personality for this turn and subsequent turns.
+    /// @deprecated `friendly` and `pragmatic` no longer select a style.
+    /// Changing this does not rewrite the thread's existing instructions.
     #[ts(optional = nullable)]
     pub personality: Option<Personality>,
     /// Optional JSON Schema used to constrain the final assistant message for
diff --git a/codex-rs/app-server/README.md b/codex-rs/app-server/README.md
index 8308b962be..beecd05576 100644
--- a/codex-rs/app-server/README.md
+++ b/codex-rs/app-server/README.md
@@ -231,6 +231,19 @@ Read the selection from `threadSettings.disabledPluginIds` in
 across resume. Forks restore the selection from the history retained at the
 requested fork boundary.
 
+# Deprecated thread personality setting
+
+`thread/start`, `thread/resume`, `thread/settings/update`, and `turn/start` still
+accept `personality`, but `friendly` and `pragmatic` no longer select a style.
+`model/list` returns `supportsPersonality: false` for every model.
+
+`none` removes the literal `# Personality` section when Codex prepares
+instructions from the model catalog, for example when starting a thread or
+switching models. Setting `friendly` or `pragmatic` can replace a previous
+`none` setting for that purpose. Changing the setting does not rewrite the
+thread's existing instructions or change explicitly supplied base instructions.
+The old `features.personality` flag is ignored.
+
 # MCP server capabilities
 
 `mcpServerStatus/list` returns `serverCapabilities` for each initialized MCP server
diff --git a/codex-rs/app-server/src/config_manager_service_tests.rs b/codex-rs/app-server/src/config_manager_service_tests.rs
index 32611a61cb..a418909299 100644
--- a/codex-rs/app-server/src/config_manager_service_tests.rs
+++ b/codex-rs/app-server/src/config_manager_service_tests.rs
@@ -1535,7 +1535,7 @@ async fn write_value_rejects_feature_requirement_conflict() {
         CloudConfigBundleFixture::loader_with_enterprise_requirement(
             r#"
 [features]
-personality = true
+fast_mode = true
 "#,
         ),
     );
@@ -1543,7 +1543,7 @@ personality = true
     let error = service
         .write_value(ConfigValueWriteParams {
             file_path: Some(tmp.path().join(CONFIG_TOML_FILE).display().to_string()),
-            key_path: "features.personality".to_string(),
+            key_path: "features.fast_mode".to_string(),
             value: serde_json::json!(false),
             merge_strategy: MergeStrategy::Replace,
             expected_version: None,
@@ -1558,7 +1558,7 @@ personality = true
     assert!(
         error
             .to_string()
-            .contains("invalid value for `features`: `features.personality=false`"),
+            .contains("invalid value for `features`: `features.fast_mode=false`"),
         "{error}"
     );
     assert_eq!(
diff --git a/codex-rs/app-server/tests/common/config_tests.rs b/codex-rs/app-server/tests/common/config_tests.rs
index 23cfec38e8..9e485f2e6a 100644
--- a/codex-rs/app-server/tests/common/config_tests.rs
+++ b/codex-rs/app-server/tests/common/config_tests.rs
@@ -11,7 +11,7 @@ fn mock_responses_config_composes_model_provider_features_and_extra_tables() {
         .with_provider_base_url("http://127.0.0.1:1234/api/codex")
         .with_approval_policy("on-request")
         .with_sandbox_mode("workspace-write")
-        .enable_feature(Feature::Personality)
+        .enable_feature(Feature::FastMode)
         .disable_feature(Feature::ShellSnapshot)
         .with_root_config("chatgpt_base_url = \"http://127.0.0.1:1234\"")
         .with_provider_config("requires_openai_auth = true")
@@ -28,7 +28,7 @@ fn mock_responses_config_composes_model_provider_features_and_extra_tables() {
         "chatgpt_base_url = \"http://127.0.0.1:1234\"",
         "model_provider = \"openai-custom\"",
         "shell_snapshot = false",
-        "personality = true",
+        "fast_mode = true",
         "[model_providers.openai-custom]\nname = \"OpenAI\"",
         "base_url = \"http://127.0.0.1:1234/api/codex\"",
         "requires_openai_auth = true",
@@ -44,10 +44,7 @@ fn legacy_mock_responses_writer_preserves_provider_auth_and_feature_overrides()
     write_mock_responses_config_toml(
         home.path(),
         "http://127.0.0.1:1234",
-        &BTreeMap::from([
-            (Feature::Personality, true),
-            (Feature::ShellSnapshot, false),
-        ]),
+        &BTreeMap::from([(Feature::FastMode, true), (Feature::ShellSnapshot, false)]),
         /*auto_compact_limit*/ 321,
         Some(true),
         "openai",
@@ -62,7 +59,7 @@ fn legacy_mock_responses_writer_preserves_provider_auth_and_feature_overrides()
         "model_auto_compact_token_limit = 321",
         "openai_base_url = \"http://127.0.0.1:1234/v1\"",
         "shell_snapshot = false",
-        "personality = true",
+        "fast_mode = true",
         "[model_providers.openai]\nname = \"OpenAI\"",
         "supports_websockets = false",
         "requires_openai_auth = true",
diff --git a/codex-rs/app-server/tests/suite/v2/safety_check_downgrade.rs b/codex-rs/app-server/tests/suite/v2/safety_check_downgrade.rs
index 53a608cbdd..ece47b4cc9 100644
--- a/codex-rs/app-server/tests/suite/v2/safety_check_downgrade.rs
+++ b/codex-rs/app-server/tests/suite/v2/safety_check_downgrade.rs
@@ -487,6 +487,5 @@ fn create_config_toml(codex_home: &std::path::Path, server_uri: &str) -> std::io
     MockResponsesConfig::new(server_uri)
         .with_model(REQUESTED_MODEL)
         .disable_feature(Feature::RemoteModels)
-        .enable_feature(Feature::Personality)
         .write(codex_home)
 }
diff --git a/codex-rs/app-server/tests/suite/v2/thread_resume.rs b/codex-rs/app-server/tests/suite/v2/thread_resume.rs
index d53aaa6734..8638286c25 100644
--- a/codex-rs/app-server/tests/suite/v2/thread_resume.rs
+++ b/codex-rs/app-server/tests/suite/v2/thread_resume.rs
@@ -1178,13 +1178,9 @@ stream_max_retries = 0
 async fn thread_resume_preserves_goal_first_and_fork_approvals_reviewer() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(codex_home.path())?;
 
     let (thread_id, fork_thread_id) = {
         let mut mcp = TestAppServer::builder()
@@ -1271,6 +1267,7 @@ async fn thread_resume_preserves_goal_first_and_fork_approvals_reviewer() -> Res
         (thread.id, fork_thread.id)
     };
 
+    let config_path = codex_home.path().join("config.toml");
     let config = std::fs::read_to_string(&config_path)?;
     std::fs::write(
         config_path,
@@ -1943,13 +1940,9 @@ fn write_dev_permission_config(
 async fn thread_goal_get_rejects_unmaterialized_thread() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -2244,13 +2237,9 @@ async fn goal_first_live_thread_appears_in_state_db_thread_list() -> Result<()>
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
     let codex_home_path = normalized_existing_path(codex_home.path())?;
-    mock_responses_config(&server.uri()).write(&codex_home_path)?;
-    let config_path = codex_home_path.join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(&codex_home_path)?;
 
     let sqlite_home = codex_home_path
         .as_path()
@@ -3000,13 +2989,9 @@ async fn thread_resume_keeps_tool_paused_goal_paused() -> Result<()> {
     ])
     .await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -3088,14 +3073,10 @@ async fn thread_resume_keeps_tool_paused_goal_paused() -> Result<()> {
 async fn thread_goal_set_enforces_configured_maximum_token_budget() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    let config = config.replace("personality = true\n", "personality = true\ngoals = true\n");
-    std::fs::write(
-        config_path,
-        format!("{config}\n[goals]\nmax_goal_token_budget = 200\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .with_extra_config("[goals]\nmax_goal_token_budget = 200")
+        .write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -3185,13 +3166,9 @@ async fn thread_goal_set_enforces_configured_maximum_token_budget() -> Result<()
 async fn thread_goal_set_preserves_budget_limited_same_objective() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -3275,13 +3252,9 @@ async fn thread_goal_set_preserves_budget_limited_same_objective() -> Result<()>
 async fn thread_goal_set_persists_resumable_stopped_statuses() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -3357,13 +3330,9 @@ async fn thread_goal_set_persists_resumable_stopped_statuses() -> Result<()> {
 async fn thread_goal_set_edits_objective_without_resetting_usage() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;
     let codex_home = TempDir::new()?;
-    mock_responses_config(&server.uri()).write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
+    mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
+        .write(codex_home.path())?;
     let thread_id = create_fake_rollout(
         codex_home.path(),
         "2025-01-05T12-00-00",
@@ -3686,14 +3655,9 @@ async fn thread_goal_lifecycle_emits_analytics_and_clear_deletes_goal() -> Resul
     .await;
     let codex_home = TempDir::new()?;
     mock_responses_config(&server.uri())
+        .enable_feature(Feature::Goals)
         .with_root_config(&format!(r#"chatgpt_base_url = "{}""#, server.uri()))
         .write(codex_home.path())?;
-    let config_path = codex_home.path().join("config.toml");
-    let config = std::fs::read_to_string(&config_path)?;
-    std::fs::write(
-        &config_path,
-        config.replace("personality = true\n", "personality = true\ngoals = true\n"),
-    )?;
     mount_analytics_capture(&server, codex_home.path()).await?;
 
     let mut mcp = TestAppServer::builder()
@@ -6263,9 +6227,7 @@ async fn thread_resume_accepts_deprecated_personality_override() -> Result<()> {
 }
 
 fn mock_responses_config(server_uri: &str) -> MockResponsesConfig {
-    MockResponsesConfig::new(server_uri)
-        .with_model("gpt-5.4")
-        .enable_feature(Feature::Personality)
+    MockResponsesConfig::new(server_uri).with_model("gpt-5.4")
 }
 
 #[allow(dead_code)]
diff --git a/codex-rs/app-server/tests/suite/v2/turn_start.rs b/codex-rs/app-server/tests/suite/v2/turn_start.rs
index 311b59cdae..5fb3091860 100644
--- a/codex-rs/app-server/tests/suite/v2/turn_start.rs
+++ b/codex-rs/app-server/tests/suite/v2/turn_start.rs
@@ -842,9 +842,7 @@ async fn turn_start_sends_originator_header() -> Result<()> {
     let server = create_mock_responses_server_sequence_unchecked(responses).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -911,9 +909,7 @@ async fn turn_start_emits_user_message_item_with_text_elements() -> Result<()> {
     let server = create_mock_responses_server_sequence_unchecked(responses).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -989,9 +985,7 @@ async fn turn_start_emits_thread_scoped_warning_notification_for_trimmed_skills(
     let server = create_mock_responses_server_sequence_unchecked(responses).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
     write_models_cache(codex_home.path()).await?;
     let cache_path = codex_home.path().join("models_cache.json");
     let mut cache: serde_json::Value =
@@ -1826,9 +1820,7 @@ async fn turn_start_accepts_text_at_limit_with_mention_item() -> Result<()> {
     let server = create_mock_responses_server_sequence_unchecked(responses).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -1876,9 +1868,7 @@ async fn turn_start_accepts_text_at_limit_with_mention_item() -> Result<()> {
 #[tokio::test]
 async fn turn_start_rejects_combined_oversized_text_input() -> Result<()> {
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new("http://localhost/unused")
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new("http://localhost/unused").write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -1969,9 +1959,7 @@ async fn turn_start_rejects_combined_oversized_text_input() -> Result<()> {
 #[tokio::test]
 async fn turn_start_rejects_invalid_permission_selection_before_starting_turn() -> Result<()> {
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new("http://localhost/unused")
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new("http://localhost/unused").write(codex_home.path())?;
     std::fs::write(
         codex_home.path().join("managed_config.toml"),
         "sandbox_mode = \"read-only\"\n",
@@ -2403,9 +2391,7 @@ async fn turn_start_emits_notifications_and_accepts_model_override() -> Result<(
     let server = create_mock_responses_server_sequence_unchecked(responses).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -2679,9 +2665,7 @@ async fn turn_start_accepts_deprecated_personality_override_v2() -> Result<()> {
     let response_mock = responses::mount_sse_once(&server, body).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -2892,9 +2876,7 @@ async fn turn_start_ignores_personality_change_mid_thread_v2() -> Result<()> {
     let response_mock = responses::mount_sse_sequence(&server, vec![sse1, sse2]).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let mut mcp = TestAppServer::builder()
         .with_codex_home(codex_home.path())
@@ -5762,9 +5744,7 @@ async fn turn_start_with_elevated_override_does_not_persist_project_trust() -> R
     let server = create_mock_responses_server_sequence_unchecked(responses).await;
 
     let codex_home = TempDir::new()?;
-    MockResponsesConfig::new(&server.uri())
-        .enable_feature(Feature::Personality)
-        .write(codex_home.path())?;
+    MockResponsesConfig::new(&server.uri()).write(codex_home.path())?;
 
     let workspace = TempDir::new()?;
 
diff --git a/codex-rs/config/src/config_toml.rs b/codex-rs/config/src/config_toml.rs
index d881c2d693..d5572f3ccd 100644
--- a/codex-rs/config/src/config_toml.rs
+++ b/codex-rs/config/src/config_toml.rs
@@ -383,7 +383,7 @@ pub struct ConfigToml {
     /// Per-thread `config` overrides are accepted but do not reapply this (no-ops).
     pub model_catalog_json: Option<AbsolutePathBuf>,
 
-    /// Optionally specify a personality for the model
+    /// Deprecated: `friendly` and `pragmatic` no longer select a style.
     pub personality: Option<Personality>,
 
     /// Optional explicit service tier request id for new turns (for example
diff --git a/codex-rs/config/src/profile_toml.rs b/codex-rs/config/src/profile_toml.rs
index 076e19c364..5016470342 100644
--- a/codex-rs/config/src/profile_toml.rs
+++ b/codex-rs/config/src/profile_toml.rs
@@ -39,6 +39,7 @@ pub struct ConfigProfile {
     pub model_verbosity: Option<Verbosity>,
     /// Optional path to a JSON model catalog (applied on startup only).
     pub model_catalog_json: Option<AbsolutePathBuf>,
+    /// Deprecated: `friendly` and `pragmatic` no longer select a style.
     pub personality: Option<Personality>,
     pub chatgpt_base_url: Option<String>,
     /// Optional path to a file containing model instructions.
diff --git a/codex-rs/core/config.schema.json b/codex-rs/core/config.schema.json
index 724a0ccbf9..5058ed4875 100644
--- a/codex-rs/core/config.schema.json
+++ b/codex-rs/core/config.schema.json
@@ -1164,7 +1164,12 @@
           "type": "string"
         },
         "personality": {
-          "$ref": "#/definitions/Personality"
+          "allOf": [
+            {
+              "$ref": "#/definitions/Personality"
+            }
+          ],
+          "description": "Deprecated: `friendly` and `pragmatic` no longer select a style."
         },
         "plan_mode_reasoning_effort": {
           "$ref": "#/definitions/ReasoningEffort"
@@ -3200,6 +3205,7 @@
       "type": "object"
     },
     "Personality": {
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style.",
       "enum": [
         "none",
         "friendly",
@@ -7028,7 +7034,7 @@
           "$ref": "#/definitions/Personality"
         }
       ],
-      "description": "Optionally specify a personality for the model"
+      "description": "Deprecated: `friendly` and `pragmatic` no longer select a style."
     },
     "plan_mode_reasoning_effort": {
       "$ref": "#/definitions/ReasoningEffort"
diff --git a/codex-rs/core/src/agent/role.rs b/codex-rs/core/src/agent/role.rs
index 18c153b32f..f6633e7590 100644
--- a/codex-rs/core/src/agent/role.rs
+++ b/codex-rs/core/src/agent/role.rs
@@ -94,7 +94,6 @@ async fn apply_role_to_config_inner(
                 && let Some(
                     feature @ (Feature::ShellTool
                     | Feature::Apps
-                    | Feature::Personality
                     | Feature::Plugins
                     | Feature::MemoryTool
                     | Feature::RequestPermissionsTool),
@@ -222,10 +221,8 @@ mod role_overrides {
         {
             next_config.include_skill_instructions = false;
         }
-        let strips_baked_personality = |config: &Config| {
-            config.features.enabled(Feature::Personality)
-                && config.personality == Some(Personality::None)
-        };
+        let strips_baked_personality =
+            |config: &Config| config.personality == Some(Personality::None);
         if strips_baked_personality(config) != strips_baked_personality(&next_config)
             && matches!(
                 config.base_instructions_provenance,
diff --git a/codex-rs/core/src/agent/role_tests.rs b/codex-rs/core/src/agent/role_tests.rs
index ba8a5de67a..fad4e30459 100644
--- a/codex-rs/core/src/agent/role_tests.rs
+++ b/codex-rs/core/src/agent/role_tests.rs
@@ -250,6 +250,22 @@ async fn apply_role_refreshes_model_instructions_only_when_personality_opt_out_c
             },
             false,
         ),
+        (
+            "none",
+            "[features]\npersonality = false",
+            BaseInstructionsProvenance::Model {
+                model: "parent-model".to_string(),
+            },
+            false,
+        ),
+        (
+            "friendly",
+            "personality = \"none\"\n[features]\npersonality = false",
+            BaseInstructionsProvenance::Model {
+                model: "parent-model".to_string(),
+            },
+            true,
+        ),
         (
             "friendly",
             "personality = \"pragmatic\"",
diff --git a/codex-rs/core/src/config/config_tests.rs b/codex-rs/core/src/config/config_tests.rs
index cafb0ff6fe..748ecc8410 100644
--- a/codex-rs/core/src/config/config_tests.rs
+++ b/codex-rs/core/src/config/config_tests.rs
@@ -11201,7 +11201,7 @@ async fn feature_requirements_normalize_effective_feature_values() -> std::io::R
             CloudConfigBundleFixture::loader_with_enterprise_requirement(
                 r#"
 [features]
-personality = true
+view_image = true
 shell_tool = false
 use_xaa = true
 "#,
@@ -11210,7 +11210,7 @@ use_xaa = true
         .build()
         .await?;
 
-    assert!(config.features.enabled(Feature::Personality));
+    assert!(config.features.enabled(Feature::ViewImage));
     assert!(!config.features.enabled(Feature::ShellTool));
     assert!(
         !config
@@ -11396,7 +11396,7 @@ async fn explicit_feature_config_is_normalized_by_requirements() -> std::io::Res
         codex_home.path().join(CONFIG_TOML_FILE),
         r#"
 [features]
-personality = false
+view_image = false
 shell_tool = true
 "#,
     )?;
@@ -11408,7 +11408,7 @@ shell_tool = true
             CloudConfigBundleFixture::loader_with_enterprise_requirement(
                 r#"
 [features]
-personality = true
+view_image = true
 shell_tool = false
 "#,
             ),
@@ -11416,7 +11416,7 @@ shell_tool = false
         .build()
         .await?;
 
-    assert!(config.features.enabled(Feature::Personality));
+    assert!(config.features.enabled(Feature::ViewImage));
     assert!(!config.features.enabled(Feature::ShellTool));
     assert!(
         !config
@@ -11430,6 +11430,55 @@ shell_tool = false
     Ok(())
 }
 
+#[test]
+fn retired_personality_feature_requirements_do_not_reject_configured_values() -> std::io::Result<()>
+{
+    for (configured, required) in [(true, false), (false, true)] {
+        let cfg: ConfigToml = toml::from_str(&format!(
+            "[features]\npersonality = {configured}\nshell_tool = false\n"
+        ))
+        .expect("valid config");
+        let requirement = Sourced::new(
+            FeatureRequirementsToml {
+                entries: BTreeMap::from([
+                    ("personality".to_string(), required),
+                    ("shell_tool".to_string(), false),
+                ]),
+            },
+            RequirementSource::EnterpriseManaged {
+                id: "enterprise-id".to_string(),
+                name: "enterprise".to_string(),
+            },
+        );
+        validate_feature_requirements_for_config_toml(&cfg, Some(&requirement))?;
+
+        let configured_features = Features::from_sources(
+            FeatureConfigSource {
+                features: cfg.features.as_ref(),
+                ..Default::default()
+            },
+            FeatureConfigSource::default(),
+            FeatureOverrides::default(),
+        );
+        let mut warnings = Vec::new();
+        let features = ManagedFeatures::from_configured_with_warnings(
+            configured_features,
+            Some(requirement),
+            &mut warnings,
+        )?;
+        assert_eq!(
+            (
+                features.enabled(Feature::Personality),
+                features.enabled(Feature::ShellTool),
+                warnings,
+            ),
+            (false, false, Vec::new()),
+        );
+    }
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn approvals_reviewer_defaults_to_manual_only_without_guardian_feature() -> std::io::Result<()>
 {
@@ -12327,7 +12376,7 @@ async fn feature_requirements_normalize_runtime_feature_mutations() -> std::io::
             CloudConfigBundleFixture::loader_with_enterprise_requirement(
                 r#"
 [features]
-personality = true
+view_image = true
 shell_tool = false
 "#,
             ),
@@ -12337,7 +12386,7 @@ shell_tool = false
 
     let mut requested = config.features.get().clone();
     requested
-        .disable(Feature::Personality)
+        .disable(Feature::ViewImage)
         .enable(Feature::ShellTool);
     assert!(config.features.can_set(&requested).is_ok());
     config
@@ -12345,7 +12394,7 @@ shell_tool = false
         .set(requested)
         .expect("managed feature mutations should normalize successfully");
 
-    assert!(config.features.enabled(Feature::Personality));
+    assert!(config.features.enabled(Feature::ViewImage));
     assert!(!config.features.enabled(Feature::ShellTool));
 
     Ok(())
diff --git a/codex-rs/core/src/config/managed_features.rs b/codex-rs/core/src/config/managed_features.rs
index 645bccd0e4..3d0e2828f6 100644
--- a/codex-rs/core/src/config/managed_features.rs
+++ b/codex-rs/core/src/config/managed_features.rs
@@ -218,6 +218,9 @@ fn parse_feature_requirements(
 ) -> BTreeMap<Feature, bool> {
     let mut pinned_features = BTreeMap::new();
     for (key, enabled) in feature_requirements.entries {
+        if key == Feature::Personality.key() {
+            continue;
+        }
         if key == "auto_review" {
             pinned_features.insert(Feature::GuardianApproval, enabled);
             continue;
diff --git a/codex-rs/core/src/config/mod.rs b/codex-rs/core/src/config/mod.rs
index 869a992cd7..ef972143cf 100644
--- a/codex-rs/core/src/config/mod.rs
+++ b/codex-rs/core/src/config/mod.rs
@@ -640,7 +640,7 @@ pub struct Config {
     /// Info needed to make an API request to the model.
     pub model_provider: ModelProviderInfo,
 
-    /// Optionally specify the personality of the model
+    /// Deprecated: `friendly` and `pragmatic` no longer select a style.
     pub personality: Option<Personality>,
 
     /// Effective permission configuration for shell tool execution.
@@ -1622,7 +1622,6 @@ impl Config {
                     Some(BaseInstructionsProvenance::Model { .. })
                 )
             }),
-            personality_enabled: self.features.enabled(Feature::Personality),
             personality: self.personality,
             model_catalog: self.model_catalog.clone(),
         }
@@ -2575,6 +2574,7 @@ pub struct ConfigOverrides {
     pub default_zsh_path: Option<AbsolutePathBuf>,
     pub base_instructions: Option<String>,
     pub developer_instructions: Option<String>,
+    /// Deprecated: `friendly` and `pragmatic` no longer select a style.
     pub personality: Option<Personality>,
     pub compact_prompt: Option<String>,
     pub show_raw_agent_reasoning: Option<bool>,
diff --git a/codex-rs/core/src/session/step_activation.rs b/codex-rs/core/src/session/step_activation.rs
index 7af13b412c..9a4e461ab6 100644
--- a/codex-rs/core/src/session/step_activation.rs
+++ b/codex-rs/core/src/session/step_activation.rs
@@ -374,7 +374,6 @@ impl Session {
                 &constraints,
                 self.services.models_manager.as_ref(),
                 &overrides,
-                self.features.enabled(Feature::Personality),
                 self.features.enabled(Feature::FastMode),
             )
             .await
diff --git a/codex-rs/core/src/session/step_activation_tests.rs b/codex-rs/core/src/session/step_activation_tests.rs
index dcaa598eb6..864886af60 100644
--- a/codex-rs/core/src/session/step_activation_tests.rs
+++ b/codex-rs/core/src/session/step_activation_tests.rs
@@ -513,10 +513,9 @@ async fn submitted_sparse_updates_preserve_captured_steps_and_ordering() {
     let model_manager_config = {
         let state = session.state.lock().await;
         let configuration = &state.session_configuration;
-        configuration.model_info_overrides.models_manager_config(
-            configuration.step_settings.personality,
-            session.features.enabled(Feature::Personality),
-        )
+        configuration
+            .model_info_overrides
+            .models_manager_config(configuration.step_settings.personality)
     };
     let expected_destination = with_config_overrides(expected_destination, &model_manager_config);
     let desired = desired_step_settings(&session).await;
diff --git a/codex-rs/core/src/session/step_settings.rs b/codex-rs/core/src/session/step_settings.rs
index 87d8d1d10e..c915037a17 100644
--- a/codex-rs/core/src/session/step_settings.rs
+++ b/codex-rs/core/src/session/step_settings.rs
@@ -129,7 +129,6 @@ impl ResolvedStepSettings {
         constraints: &StepSettingsConstraints<'_>,
         models_manager: &dyn ModelsManager,
         overrides: &ModelInfoOverrides,
-        personality_enabled: bool,
         fast_mode_enabled: bool,
     ) -> ConstraintResult<Self> {
         let selected = self.selected.apply(update, constraints)?;
@@ -139,11 +138,7 @@ impl ResolvedStepSettings {
         {
             Arc::clone(&self.model_info)
         } else {
-            Arc::new(
-                selected
-                    .resolve_model_info(models_manager, overrides, personality_enabled)
-                    .await,
-            )
+            Arc::new(selected.resolve_model_info(models_manager, overrides).await)
         };
         let mut next = Self::new(Arc::new(selected), model_info, fast_mode_enabled);
         next.mcp_approvals_reviewer_override = update
@@ -206,7 +201,6 @@ impl ModelInfoOverrides {
     pub(crate) fn models_manager_config(
         &self,
         personality: Option<Personality>,
-        personality_enabled: bool,
     ) -> ModelsManagerConfig {
         ModelsManagerConfig {
             model_context_window: self.context_window,
@@ -214,7 +208,6 @@ impl ModelInfoOverrides {
             tool_output_token_limit: self.tool_output_token_limit,
             base_instructions: self.base_instructions.clone(),
             personality,
-            personality_enabled,
             // The models manager already owns its catalog.
             model_catalog: None,
         }
@@ -254,9 +247,8 @@ impl StepSettings {
         &self,
         models_manager: &dyn ModelsManager,
         overrides: &ModelInfoOverrides,
-        personality_enabled: bool,
     ) -> ModelInfo {
-        let config = overrides.models_manager_config(self.personality, personality_enabled);
+        let config = overrides.models_manager_config(self.personality);
         models_manager
             .get_model_info(self.collaboration_mode.model(), &config)
             .await
diff --git a/codex-rs/core/src/session/step_settings_tests.rs b/codex-rs/core/src/session/step_settings_tests.rs
index 72584a146e..1779136d00 100644
--- a/codex-rs/core/src/session/step_settings_tests.rs
+++ b/codex-rs/core/src/session/step_settings_tests.rs
@@ -451,28 +451,14 @@ async fn model_resolution_preserves_startup_overrides_and_instruction_provenance
     // Capture the same filtered explicit overrides that session startup owns.
     let overrides = ModelInfoOverrides::from(config.to_models_manager_config());
 
-    for (personality, personality_enabled, catalog_instructions) in [
+    for (personality, catalog_instructions) in [
         (
             Personality::Friendly,
-            true,
-            "Catalog B.\n# Personality\nfixed\n# Rules\nKeep the rules.",
-        ),
-        (
-            Personality::None,
-            true,
-            "Catalog B.\n# Rules\nKeep the rules.",
-        ),
-        (
-            Personality::Friendly,
-            false,
             "Catalog B.\n# Personality\nfixed\n# Rules\nKeep the rules.",
         ),
+        (Personality::None, "Catalog B.\n# Rules\nKeep the rules."),
     ] {
         config.personality = Some(personality);
-        config
-            .features
-            .set_enabled(Feature::Personality, personality_enabled)
-            .expect("test config should allow personality changes");
         let mut settings = configured_settings();
         settings.collaboration_mode = settings.collaboration_mode.with_updates(
             Some("model-b".to_string()),
@@ -485,11 +471,7 @@ async fn model_resolution_preserves_startup_overrides_and_instruction_provenance
             .get_model_info("model-b", &config.to_models_manager_config())
             .await;
         let resolved = settings
-            .resolve_model_info(
-                &models_manager,
-                &overrides,
-                config.features.enabled(Feature::Personality),
-            )
+            .resolve_model_info(&models_manager, &overrides)
             .await;
         assert_eq!(resolved, legacy);
         assert_eq!(
diff --git a/codex-rs/core/src/session/turn_context.rs b/codex-rs/core/src/session/turn_context.rs
index d8a6c34fc7..e5a21b6e8e 100644
--- a/codex-rs/core/src/session/turn_context.rs
+++ b/codex-rs/core/src/session/turn_context.rs
@@ -1018,7 +1018,6 @@ impl Session {
             .resolve_model_info(
                 self.services.models_manager.as_ref(),
                 &session_configuration.model_info_overrides,
-                self.features.enabled(Feature::Personality),
             )
             .await;
         let multi_agent_version = match multi_agent_runtime {
diff --git a/codex-rs/core/tests/suite/model_switching.rs b/codex-rs/core/tests/suite/model_switching.rs
index a7a4493e94..23cd535e65 100644
--- a/codex-rs/core/tests/suite/model_switching.rs
+++ b/codex-rs/core/tests/suite/model_switching.rs
@@ -181,14 +181,8 @@ async fn first_turn_model_change_appends_model_instructions_developer_message(
     let server = MockServer::start().await;
     let resp_mock = mount_sse_once(&server, sse_completed("resp-1")).await;
 
-    let mut builder = test_codex()
-        .with_model_info_override("gpt-5.6-terra", configure_model_switching_fixture)
-        .with_config(|config| {
-            config
-                .features
-                .enable(Feature::Personality)
-                .expect("test config should allow feature update");
-        });
+    let mut builder =
+        test_codex().with_model_info_override("gpt-5.6-terra", configure_model_switching_fixture);
     let test = builder.build_with_auto_env(&server).await?;
     let next_model = "gpt-5.5";
 
@@ -401,12 +395,7 @@ async fn model_change_with_legacy_personality_override_only_appends_model_instru
     )
     .await;
 
-    let mut builder = test_codex().with_model("gpt-5.5").with_config(|config| {
-        config
-            .features
-            .enable(Feature::Personality)
-            .expect("test config should allow feature update");
-    });
+    let mut builder = test_codex().with_model("gpt-5.5");
     let test = builder.build(&server).await?;
     let next_model = "exp-codex-personality";
 
diff --git a/codex-rs/core/tests/suite/model_visible_layout.rs b/codex-rs/core/tests/suite/model_visible_layout.rs
index 38cd360ddf..bcc0601ff2 100644
--- a/codex-rs/core/tests/suite/model_visible_layout.rs
+++ b/codex-rs/core/tests/suite/model_visible_layout.rs
@@ -549,10 +549,6 @@ async fn snapshot_model_visible_layout_resume_with_personality_change() -> Resul
         .with_config(|config| {
             config.update_plan_enabled = true;
             config.model = Some("gpt-5.4".to_string());
-            config
-                .features
-                .enable(Feature::Personality)
-                .expect("test config should allow feature update");
             config.personality = Some(Personality::Pragmatic);
         });
     let resumed = resume_builder.restart(&server, &initial).await?;
diff --git a/codex-rs/core/tests/suite/personality.rs b/codex-rs/core/tests/suite/personality.rs
index 62bf008f73..b8e1985882 100644
--- a/codex-rs/core/tests/suite/personality.rs
+++ b/codex-rs/core/tests/suite/personality.rs
@@ -1,6 +1,5 @@
 use codex_config::types::Personality;
 use codex_core::TurnInputRequest;
-use codex_features::Feature;
 use codex_protocol::config_types::CollaborationMode;
 use codex_protocol::config_types::ModeKind;
 use codex_protocol::config_types::Settings;
@@ -64,10 +63,6 @@ async fn config_personality_none_sends_no_personality() -> anyhow::Result<()> {
     let server = start_mock_server().await;
     let resp_mock = mount_sse_once(&server, sse_completed("resp-1")).await;
     let mut builder = test_codex().with_model("gpt-5.5").with_config(|config| {
-        config
-            .features
-            .enable(Feature::Personality)
-            .expect("test config should allow feature update");
         config.personality = Some(Personality::None);
     });
     let test = builder.build(&server).await?;
@@ -106,8 +101,13 @@ async fn config_personality_none_sends_no_personality() -> anyhow::Result<()> {
     Ok(())
 }
 
+#[test_case(None; "without feature config")]
+#[test_case(Some(false); "with removed feature disabled")]
+#[test_case(Some(true); "with removed feature enabled")]
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn config_personality_none_strips_baked_personality_section() -> anyhow::Result<()> {
+async fn config_personality_none_strips_baked_personality_section(
+    legacy_feature_setting: Option<bool>,
+) -> anyhow::Result<()> {
     skip_if_no_network!(Ok(()));
 
     let server = start_mock_server().await;
@@ -119,14 +119,14 @@ async fn config_personality_none_strips_baked_personality_section() -> anyhow::R
                 model_messages.instructions_variables = None;
             }
         })
-        .with_config(|config| {
-            config
-                .features
-                .enable(Feature::Personality)
-                .expect("test config should allow feature update");
-            config.personality = Some(Personality::None);
+        .with_pre_build_hook(move |home| {
+            let mut config = "personality = \"none\"\n".to_string();
+            if let Some(value) = legacy_feature_setting {
+                config.push_str(&format!("[features]\npersonality = {value}\n"));
+            }
+            std::fs::write(home.join("config.toml"), config).expect("write personality config");
         });
-    let test = builder.build(&server).await?;
+    let test = builder.build_with_auto_env(&server).await?;
 
     test.codex
         .start_or_steer_turn(read_only_text_turn(
@@ -152,7 +152,7 @@ async fn config_personality_none_strips_baked_personality_section() -> anyhow::R
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn config_personality_none_preserves_explicit_base_instructions(
     custom_instructions: &'static str,
-    personality_enabled: bool,
+    legacy_feature_setting: bool,
 ) -> anyhow::Result<()> {
     skip_if_no_network!(Ok(()));
 
@@ -160,12 +160,13 @@ async fn config_personality_none_preserves_explicit_base_instructions(
     let resp_mock = mount_sse_once(&server, sse_completed("resp-1")).await;
     let mut builder = test_codex()
         .with_model("gpt-5.5")
+        .with_pre_build_hook(move |home| {
+            let config = format!(
+                "personality = \"none\"\n[features]\npersonality = {legacy_feature_setting}\n"
+            );
+            std::fs::write(home.join("config.toml"), config).expect("write personality config");
+        })
         .with_config(move |config| {
-            config
-                .features
-                .set_enabled(Feature::Personality, personality_enabled)
-                .expect("test config should allow feature update");
-            config.personality = Some(Personality::None);
             config.base_instructions = Some(custom_instructions.to_string());
         });
     let test = builder.build_with_auto_env(&server).await?;
@@ -198,12 +199,7 @@ async fn default_instructions_are_friendly_without_config_toml() -> anyhow::Resu
 
     let server = start_mock_server().await;
     let resp_mock = mount_sse_once(&server, sse_completed("resp-1")).await;
-    let mut builder = test_codex().with_model("gpt-5.5").with_config(|config| {
-        config
-            .features
-            .enable(Feature::Personality)
-            .expect("test config should allow feature update");
-    });
+    let mut builder = test_codex().with_model("gpt-5.5");
     let test = builder.build(&server).await?;
     assert_eq!(test.config.personality, None);
 
@@ -245,10 +241,6 @@ async fn fixed_friendly_personality_ignores_pragmatic_update(
     )
     .await;
     let mut builder = test_codex().with_model(model).with_config(|config| {
-        config
-            .features
-            .enable(Feature::Personality)
-            .expect("test config should allow feature update");
         config.personality = Some(Personality::Friendly);
     });
     let test = builder.build_with_auto_env(&server).await?;
diff --git a/codex-rs/features/src/lib.rs b/codex-rs/features/src/lib.rs
index 4982f63ab2..b6355c2d8f 100644
--- a/codex-rs/features/src/lib.rs
+++ b/codex-rs/features/src/lib.rs
@@ -344,7 +344,7 @@ pub enum Feature {
     AuthElicitation,
     /// Offer Amazon Bedrock setup during TUI sign-in onboarding.
     BedrockSetupWizard,
-    /// Enable personality selection in the TUI.
+    /// Removed compatibility flag retained as a no-op.
     Personality,
     /// Enable native artifact tools.
     Artifact,
@@ -610,7 +610,7 @@ impl Features {
                 "image_detail_original" | "resize_all_images" | "item_ids" => {
                     continue;
                 }
-                "plugin_hooks" => {
+                "personality" | "plugin_hooks" => {
                     continue;
                 }
                 "skill_env_var_dependency_prompt" => {
@@ -1688,8 +1688,8 @@ pub const FEATURES: &[FeatureSpec] = &[
     FeatureSpec {
         id: Feature::Personality,
         key: "personality",
-        stage: Stage::Stable,
-        default_enabled: true,
+        stage: Stage::Removed,
+        default_enabled: false,
     },
     FeatureSpec {
         id: Feature::Artifact,
diff --git a/codex-rs/features/src/tests.rs b/codex-rs/features/src/tests.rs
index 74e2e31b89..52437315dd 100644
--- a/codex-rs/features/src/tests.rs
+++ b/codex-rs/features/src/tests.rs
@@ -645,6 +645,35 @@ fn from_sources_ignores_removed_apply_patch_freeform_feature_key() {
     assert_eq!(features, Features::with_defaults());
 }
 
+#[test]
+fn from_sources_accepts_and_ignores_removed_personality_feature_values() {
+    for enabled in [false, true] {
+        let features_toml: FeaturesToml = toml::from_str(&format!("personality = {enabled}"))
+            .expect("legacy personality feature should deserialize");
+        let source = FeatureConfigSource {
+            features: Some(&features_toml),
+            ..Default::default()
+        };
+
+        assert_eq!(
+            Features::from_sources(
+                source,
+                FeatureConfigSource::default(),
+                FeatureOverrides::default(),
+            ),
+            Features::with_defaults()
+        );
+        assert_eq!(
+            Features::from_sources(
+                FeatureConfigSource::default(),
+                source,
+                FeatureOverrides::default(),
+            ),
+            Features::with_defaults()
+        );
+    }
+}
+
 #[test]
 fn from_sources_ignores_removed_plugin_hooks_feature_key() {
     let features_toml = FeaturesToml::from(BTreeMap::from([("plugin_hooks".to_string(), true)]));
@@ -796,7 +825,7 @@ fn unstable_warning_event_only_mentions_enabled_under_development_features() {
         "apply_patch_streaming_events".to_string(),
         TomlValue::Boolean(true),
     );
-    configured_features.insert("personality".to_string(), TomlValue::Boolean(true));
+    configured_features.insert("fast_mode".to_string(), TomlValue::Boolean(true));
     configured_features.insert("unknown".to_string(), TomlValue::Boolean(true));
 
     let mut features = Features::with_defaults();
@@ -814,7 +843,7 @@ fn unstable_warning_event_only_mentions_enabled_under_development_features() {
         panic!("expected warning event");
     };
     assert!(message.contains("apply_patch_streaming_events"));
-    assert!(!message.contains("personality"));
+    assert!(!message.contains("fast_mode"));
     assert!(message.contains("/tmp/config.toml"));
 }
 
diff --git a/codex-rs/models-manager/src/config.rs b/codex-rs/models-manager/src/config.rs
index 6c32d548a4..79ac9bcff1 100644
--- a/codex-rs/models-manager/src/config.rs
+++ b/codex-rs/models-manager/src/config.rs
@@ -7,7 +7,6 @@ pub struct ModelsManagerConfig {
     pub model_auto_compact_token_limit: Option<i64>,
     pub tool_output_token_limit: Option<usize>,
     pub base_instructions: Option<String>,
-    pub personality_enabled: bool,
     pub personality: Option<Personality>,
     pub model_catalog: Option<ModelsResponse>,
 }
diff --git a/codex-rs/models-manager/src/model_info.rs b/codex-rs/models-manager/src/model_info.rs
index 81538bc6b7..b9ead2bdf7 100644
--- a/codex-rs/models-manager/src/model_info.rs
+++ b/codex-rs/models-manager/src/model_info.rs
@@ -60,8 +60,7 @@ pub fn with_config_overrides(mut model: ModelInfo, config: &ModelsManagerConfig)
         });
         model_messages.instructions_template = Some(base_instructions.clone());
         model_messages.instructions_variables = None;
-    } else if config.personality_enabled
-        && config.personality == Some(Personality::None)
+    } else if config.personality == Some(Personality::None)
         && let Some(instructions_template) = model
             .model_messages
             .as_mut()
diff --git a/codex-rs/models-manager/src/model_info_tests.rs b/codex-rs/models-manager/src/model_info_tests.rs
index 012b0fbf68..69fabe659c 100644
--- a/codex-rs/models-manager/src/model_info_tests.rs
+++ b/codex-rs/models-manager/src/model_info_tests.rs
@@ -18,7 +18,6 @@ use pretty_assertions::assert_eq;
 
 fn config_with_personality(personality: Option<Personality>) -> ModelsManagerConfig {
     ModelsManagerConfig {
-        personality_enabled: true,
         personality,
         ..Default::default()
     }
@@ -26,7 +25,7 @@ fn config_with_personality(personality: Option<Personality>) -> ModelsManagerCon
 
 #[test]
 fn base_instruction_override_is_literal_and_preserves_catalog_messages() {
-    let override_instructions = "override {{ personality }}";
+    let override_instructions = "override {{ personality }}\n# Personality\nKeep me";
     let persistent_instructions = "Follow up on the active task.";
     let async_message_description = "Catalog async message description.";
     let mut model = model_info_from_slug("unknown-model");
@@ -104,6 +103,7 @@ fn base_instruction_override_is_literal_and_preserves_catalog_messages() {
     });
     let config = ModelsManagerConfig {
         base_instructions: Some(override_instructions.to_string()),
+        personality: Some(Personality::None),
         ..Default::default()
     };
 
@@ -131,7 +131,7 @@ fn base_instruction_override_is_literal_and_preserves_catalog_messages() {
         })
     );
     assert_eq!(
-        updated.get_model_instructions(/*personality*/ None),
+        updated.get_model_instructions(Some(Personality::None)),
         override_instructions
     );
 }
@@ -193,16 +193,12 @@ fn personality_none_strips_catalog_instruction_sources_through_the_next_h1() {
 }
 
 #[test]
-fn baked_personality_section_is_preserved_without_enabled_explicit_none() {
+fn baked_personality_section_is_preserved_without_explicit_none() {
     let instructions = "Intro\n# Personality\nKeep me\n# General\nKeep me too";
     let configs = [
         config_with_personality(/*personality*/ None),
         config_with_personality(Some(Personality::Friendly)),
         config_with_personality(Some(Personality::Pragmatic)),
-        ModelsManagerConfig {
-            personality: Some(Personality::None),
-            ..Default::default()
-        },
     ];
 
     for config in configs {
@@ -220,6 +216,32 @@ fn baked_personality_section_is_preserved_without_enabled_explicit_none() {
     }
 }
 
+#[test]
+fn explicit_empty_base_instructions_stay_empty_with_personality_none() {
+    let mut model = model_info_from_slug("unknown-model");
+    model
+        .model_messages
+        .as_mut()
+        .expect("fallback model messages")
+        .instructions_template = Some("Intro\n# Personality\nRemove me".to_string());
+    let config = ModelsManagerConfig {
+        base_instructions: Some(String::new()),
+        personality: Some(Personality::None),
+        ..Default::default()
+    };
+
+    let updated = with_config_overrides(model, &config);
+
+    assert_eq!(
+        updated
+            .model_messages
+            .as_ref()
+            .and_then(|messages| messages.instructions_template.as_deref()),
+        Some("")
+    );
+    assert_eq!(updated.get_model_instructions(config.personality), "");
+}
+
 #[test]
 fn unknown_model_uses_builtin_instruction_template() {
     let model = model_info_from_slug("unknown-model");
diff --git a/codex-rs/protocol/src/config_types.rs b/codex-rs/protocol/src/config_types.rs
index b5ac448ebc..87ffe6dc8b 100644
--- a/codex-rs/protocol/src/config_types.rs
+++ b/codex-rs/protocol/src/config_types.rs
@@ -311,6 +311,7 @@ pub enum WindowsSandboxProxySettingsMode {
     Preserve,
 }
 
+/// Deprecated: `friendly` and `pragmatic` no longer select a style.
 #[derive(
     Debug,
     Serialize,
diff --git a/sdk/python/docs/api-reference.md b/sdk/python/docs/api-reference.md
index 5d9c160dff..9fd42b5e7d 100644
--- a/sdk/python/docs/api-reference.md
+++ b/sdk/python/docs/api-reference.md
@@ -40,6 +40,7 @@ from openai_codex.types import (
     CancelLoginAccountStatus,
     GetAccountResponse,
     InitializeResponse,
+    Personality,
     ThreadItem,
     ThreadTokenUsage,
     TurnError,
@@ -88,6 +89,27 @@ server's default behavior. This does not remove history from the model's
 context. Both methods return a thread handle; use `thread.read(include_turns=True)`
 to retrieve its history.
 
+### Deprecated personality selection
+
+`thread_start(...)`, `thread_resume(...)`, and the thread's `run(...)` and
+`turn(...)` still accept `personality` for compatibility. The current app-server
+accepts `Personality.friendly` and `Personality.pragmatic`, but they no longer
+select a style; model instructions define the tone.
+
+Python `None` or omitting the option leaves it unset. Explicit `Personality.none`
+(wire value `"none"`) strips the literal `# Personality` section the next time
+Codex prepares instructions from the model catalog, such as when starting a
+thread or switching models. It does not change explicitly supplied base
+instructions or rewrite an existing thread's instructions when resuming or
+starting a turn. Either legacy value can replace a previous `Personality.none`
+setting for future model instructions. The old `features.personality` flag is
+ignored.
+
+Models returned by `models(...)` still expose `supports_personality` for
+compatibility. This field is deprecated and always `False` on the current
+app-server; it describes selectable personality, not the separate
+`Personality.none` opt-out.
+
 ## AsyncCodex (async parity)
 
 ```python
@@ -121,6 +143,9 @@ Properties/methods:
 - `thread_unarchive(thread_id: str) -> Awaitable[AsyncThread]`
 - `models(*, include_hidden: bool = False) -> Awaitable[ModelListResponse]`
 
+The [deprecated personality selection](#deprecated-personality-selection)
+notes also apply to the async methods and model results.
+
 Async context manager:
 
 ```python
@@ -198,6 +223,7 @@ These options have the same behavior on sync and async `run(...)` and `turn(...)
 
 | Option | Behavior |
 | --- | --- |
+| `personality: Personality \| None = None` | `Personality.friendly` and `Personality.pragmatic` are deprecated and no longer select a style. See [deprecated personality selection](#deprecated-personality-selection). |
 | `service_tier: str | None = None` | Sets the thread's service tier for this and subsequent turns. |
 | `turn_service_tier: str | None = None` | Overrides the tier for a newly started turn only. `None` inherits the thread setting; `"default"` selects standard speed. Does not change the thread default and is ignored when input joins an active turn. |
 | `source: str | None = None` | Labels the caller that initiated a new turn, such as `"review_ui"`. This is metadata; it does not schedule work or grant authority. Ignored when input joins an active turn. |
diff --git a/sdk/python/src/openai_codex/api.py b/sdk/python/src/openai_codex/api.py
index d226744cf8..3ccdbfd574 100644
--- a/sdk/python/src/openai_codex/api.py
+++ b/sdk/python/src/openai_codex/api.py
@@ -297,7 +297,11 @@ class Codex:
     # END GENERATED: Codex.flat_methods
 
     def models(self, *, include_hidden: bool = False) -> ModelListResponse:
-        """List available models reported by Codex."""
+        """List available models reported by Codex.
+
+        The deprecated ``Model.supports_personality`` field is always ``False``
+        on the current app-server.
+        """
         return self._client.model_list(include_hidden=include_hidden)
 
 
@@ -557,6 +561,11 @@ class AsyncCodex:
     # END GENERATED: AsyncCodex.flat_methods
 
     async def models(self, *, include_hidden: bool = False) -> ModelListResponse:
+        """List available models reported by Codex.
+
+        The deprecated ``Model.supports_personality`` field is always ``False``
+        on the current app-server.
+        """
         await self._ensure_initialized()
         return await self._client.model_list(include_hidden=include_hidden)
 
diff --git a/sdk/python/src/openai_codex/generated/v2_all.py b/sdk/python/src/openai_codex/generated/v2_all.py
index 9250b97ae2..abe7ea4c60 100644
--- a/sdk/python/src/openai_codex/generated/v2_all.py
+++ b/sdk/python/src/openai_codex/generated/v2_all.py
@@ -5834,7 +5834,12 @@ class ThreadResumeParams(BaseModel):
         str | None, Field(description="Configuration overrides for the resumed thread, if any.")
     ] = None
     model_provider: Annotated[str | None, Field(alias="modelProvider")] = None
-    personality: Personality | None = None
+    personality: Annotated[
+        Personality | None,
+        Field(
+            description="@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
+        ),
+    ] = None
     sandbox: SandboxMode | None = None
     service_tier: Annotated[str | None, Field(alias="serviceTier")] = None
     thread_id: Annotated[str, Field(alias="threadId")]
@@ -8521,7 +8526,13 @@ class Model(BaseModel):
     supported_reasoning_efforts: Annotated[
         list[ReasoningEffortOption], Field(alias="supportedReasoningEfforts")
     ]
-    supports_personality: Annotated[bool | None, Field(alias="supportsPersonality")] = False
+    supports_personality: Annotated[
+        bool | None,
+        Field(
+            alias="supportsPersonality",
+            description="@deprecated Always false; models no longer support personality selection.",
+        ),
+    ] = False
     upgrade: str | None = None
     upgrade_info: Annotated[ModelUpgradeInfo | None, Field(alias="upgradeInfo")] = None
 
@@ -9971,7 +9982,12 @@ class ThreadSettings(BaseModel):
     effort: ReasoningEffort | None = None
     model: str
     model_provider: Annotated[str, Field(alias="modelProvider")]
-    personality: Personality | None = None
+    personality: Annotated[
+        Personality | None,
+        Field(
+            description="@deprecated Reports the saved setting; `friendly` and `pragmatic` no longer select a style."
+        ),
+    ] = None
     sandbox_policy: Annotated[SandboxPolicy, Field(alias="sandboxPolicy")]
     service_tier: Annotated[str | None, Field(alias="serviceTier")] = None
     summary: ReasoningSummary | None = None
@@ -10004,7 +10020,10 @@ class ThreadStartParams(BaseModel):
     ephemeral: bool | None = None
     model: str | None = None
     model_provider: Annotated[str | None, Field(alias="modelProvider")] = None
-    personality: Personality | None = None
+    personality: Annotated[
+        Personality | None,
+        Field(description="@deprecated `friendly` and `pragmatic` no longer select a style."),
+    ] = None
     sandbox: SandboxMode | None = None
     service_name: Annotated[str | None, Field(alias="serviceName")] = None
     service_tier: Annotated[str | None, Field(alias="serviceTier")] = None
@@ -10424,7 +10443,7 @@ class ConfigBatchWriteParams(BaseModel):
         bool | None,
         Field(
             alias="reloadUserConfig",
-            description="When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and personality defaults are not reloaded.",
+            description="When true, hot-reload updated runtime settings into loaded threads after writing. Session-static model, reasoning-effort, Plan-mode reasoning-effort, and service-tier defaults are not reloaded. The deprecated personality setting is also not reloaded.",
         ),
     ] = None
 
@@ -12141,7 +12160,9 @@ class TurnStartParams(BaseModel):
     ] = None
     personality: Annotated[
         Personality | None,
-        Field(description="Override the personality for this turn and subsequent turns."),
+        Field(
+            description="@deprecated `friendly` and `pragmatic` no longer select a style. Changing this does not rewrite the thread's existing instructions."
+        ),
     ] = None
     sandbox_policy: Annotated[
         SandboxPolicy | None,