Support changing reasoning effort

codex-rs/common/src/lib.rs

@@ -29,3 +29,5 @@ mod config_summary;
 pub use config_summary::create_config_summary_entries;
 // Shared fuzzy matcher (used by TUI selection popups and other UI filtering)
 pub mod fuzzy_match;
+// Shared model presets used by TUI and MCP server
+pub mod model_presets;

codex-rs/common/src/model_presets.rs

@@ -0,0 +1,54 @@
+use codex_core::protocol_config_types::ReasoningEffort;
+
+/// A simple preset pairing a model slug with a reasoning effort.
+#[derive(Debug, Clone, Copy)]
+pub struct ModelPreset {
+    /// Stable identifier for the preset.
+    pub id: &'static str,
+    /// Display label shown in UIs.
+    pub label: &'static str,
+    /// Short human description shown next to the label in UIs.
+    pub description: &'static str,
+    /// Model slug (e.g., "gpt-5").
+    pub model: &'static str,
+    /// Reasoning effort to apply for this preset.
+    pub effort: ReasoningEffort,
+}
+
+/// Built-in list of model presets that pair a model with a reasoning effort.
+///
+/// Keep this UI-agnostic so it can be reused by both TUI and MCP server.
+pub fn builtin_model_presets() -> &'static [ModelPreset] {
+    // Order reflects effort from minimal to high.
+    const PRESETS: &[ModelPreset] = &[
+        ModelPreset {
+            id: "gpt-5-minimal",
+            label: "gpt-5 minimal",
+            description: "— Fastest responses with very limited reasoning; ideal for coding, instructions, or lightweight tasks.",
+            model: "gpt-5",
+            effort: ReasoningEffort::Minimal,
+        },
+        ModelPreset {
+            id: "gpt-5-low",
+            label: "gpt-5 low",
+            description: "— Balances speed with some reasoning; useful for straightforward queries and short explanations.",
+            model: "gpt-5",
+            effort: ReasoningEffort::Low,
+        },
+        ModelPreset {
+            id: "gpt-5-medium",
+            label: "gpt-5 medium",
+            description: "— Default setting; provides a solid balance of reasoning depth and latency for general-purpose tasks.",
+            model: "gpt-5",
+            effort: ReasoningEffort::Medium,
+        },
+        ModelPreset {
+            id: "gpt-5-high",
+            label: "gpt-5 high",
+            description: "— Maximizes reasoning depth for complex or ambiguous problems.",
+            model: "gpt-5",
+            effort: ReasoningEffort::High,
+        },
+    ];
+    PRESETS
+}

codex-rs/config.md

@@ -217,17 +217,14 @@ Users can specify config values at multiple levels. Order of precedence is as fo
 
 ## model_reasoning_effort
 
-If the model name starts with `"o"` (as in `"o3"` or `"o4-mini"`) or `"codex"`, reasoning is enabled by default when using the Responses API. As explained in the [OpenAI Platform documentation](https://platform.openai.com/docs/guides/reasoning?api-mode=responses#get-started-with-reasoning), this can be set to:
+If the selected model is known to support reasoning (for example: `o3`, `o4-mini`, `codex-*`, `gpt-5`), reasoning is enabled by default when using the Responses API. As explained in the [OpenAI Platform documentation](https://platform.openai.com/docs/guides/reasoning?api-mode=responses#get-started-with-reasoning), this can be set to:
 
+- `"minimal"`
 - `"low"`
 - `"medium"` (default)
 - `"high"`
 
-To disable reasoning, set `model_reasoning_effort` to `"none"` in your config:
-
-```toml
-model_reasoning_effort = "none"  # disable reasoning
-```
+Note: to minimize reasoning, choose `"minimal"`.
 
 ## model_reasoning_summary
 

codex-rs/core/src/config.rs

@@ -140,8 +140,8 @@ pub struct Config {
     /// When this program is invoked, arg0 will be set to `codex-linux-sandbox`.
     pub codex_linux_sandbox_exe: Option<PathBuf>,
 
-    /// If not "none", the value to use for `reasoning.effort` when making a
-    /// request using the Responses API.
+    /// Value to use for `reasoning.effort` when making a request using the
+    /// Responses API.
     pub model_reasoning_effort: ReasoningEffort,
 
     /// If not "none", the value to use for `reasoning.summary` when making a

codex-rs/mcp-server/Cargo.toml

@@ -17,6 +17,7 @@ workspace = true
 [dependencies]
 anyhow = "1"
 codex-arg0 = { path = "../arg0" }
+codex-common = { path = "../common" }
 codex-core = { path = "../core" }
 codex-login = { path = "../login" }
 codex-protocol = { path = "../protocol" }

codex-rs/protocol/src/config_types.rs

@@ -1,10 +1,13 @@
 use serde::Deserialize;
 use serde::Serialize;
 use strum_macros::Display;
+use strum_macros::EnumIter;
 use ts_rs::TS;
 
 /// See https://platform.openai.com/docs/guides/reasoning?api-mode=responses#get-started-with-reasoning
-#[derive(Debug, Serialize, Deserialize, Default, Clone, Copy, PartialEq, Eq, Display, TS)]
+#[derive(
+    Debug, Serialize, Deserialize, Default, Clone, Copy, PartialEq, Eq, Display, TS, EnumIter,
+)]
 #[serde(rename_all = "lowercase")]
 #[strum(serialize_all = "lowercase")]
 pub enum ReasoningEffort {
@@ -13,8 +16,6 @@ pub enum ReasoningEffort {
     #[default]
     Medium,
     High,
-    /// Option to disable reasoning.
-    None,
 }
 
 /// A summary of the reasoning performed by the model. This can be useful for

codex-rs/tui/src/app.rs

@@ -382,6 +382,11 @@ impl App<'_> {
                             self.app_event_tx.send(AppEvent::CodexOp(Op::Compact));
                         }
                     }
+                    SlashCommand::Model => {
+                        if let AppState::Chat { widget } = &mut self.app_state {
+                            widget.open_model_popup();
+                        }
+                    }
                     SlashCommand::Quit => {
                         break;
                     }
@@ -499,6 +504,16 @@ impl App<'_> {
                         widget.apply_file_search_result(query, matches);
                     }
                 }
+                AppEvent::UpdateReasoningEffort(effort) => {
+                    if let AppState::Chat { widget } = &mut self.app_state {
+                        widget.set_reasoning_effort(effort);
+                    }
+                }
+                AppEvent::UpdateModel(model) => {
+                    if let AppState::Chat { widget } = &mut self.app_state {
+                        widget.set_model(model);
+                    }
+                }
             }
         }
         terminal.clear()?;

codex-rs/tui/src/app_event.rs

@@ -6,6 +6,7 @@ use std::time::Duration;
 
 use crate::app::ChatWidgetArgs;
 use crate::slash_command::SlashCommand;
+use codex_core::protocol_config_types::ReasoningEffort;
 
 #[allow(clippy::large_enum_variant)]
 #[derive(Debug)]
@@ -63,4 +64,10 @@ pub(crate) enum AppEvent {
     /// Onboarding: result of login_with_chatgpt.
     OnboardingAuthComplete(Result<(), String>),
     OnboardingComplete(ChatWidgetArgs),
+
+    /// Update the current reasoning effort in the running app and widget.
+    UpdateReasoningEffort(ReasoningEffort),
+
+    /// Update the current model slug in the running app and widget.
+    UpdateModel(String),
 }

codex-rs/tui/src/bottom_pane/command_popup.rs

@@ -71,13 +71,16 @@ impl CommandPopup {
             for (_, cmd) in self.all_commands.iter() {
                 out.push((cmd, None, 0));
             }
+            // Keep the original presentation order when no filter is applied.
+            return out;
         } else {
             for (_, cmd) in self.all_commands.iter() {
                 if let Some((indices, score)) = fuzzy_match(cmd.command(), filter) {
                     out.push((cmd, Some(indices), score));
                 }
             }
         }
+        // When filtering, sort by ascending score and then by command for stability.
         out.sort_by(|a, b| a.2.cmp(&b.2).then_with(|| a.0.command().cmp(b.0.command())));
         out
     }
@@ -128,7 +131,7 @@ impl WidgetRef for CommandPopup {
                 })
                 .collect()
         };
-        render_rows(area, buf, &rows_all, &self.state, MAX_POPUP_ROWS);
+        render_rows(area, buf, &rows_all, &self.state, MAX_POPUP_ROWS, false);
     }
 }
 

codex-rs/tui/src/bottom_pane/file_search_popup.rs

@@ -134,9 +134,9 @@ impl WidgetRef for &FileSearchPopup {
 
         if self.waiting && rows_all.is_empty() {
             // Render a minimal waiting stub using the shared renderer (no rows -> "no matches").
-            render_rows(area, buf, &[], &self.state, MAX_POPUP_ROWS);
+            render_rows(area, buf, &[], &self.state, MAX_POPUP_ROWS, false);
         } else {
-            render_rows(area, buf, &rows_all, &self.state, MAX_POPUP_ROWS);
+            render_rows(area, buf, &rows_all, &self.state, MAX_POPUP_ROWS, false);
         }
     }
 }