Always send reasoning parameters in Responses requests (#32206)

## What changed

- Build a reasoning payload for every Responses request and always include `reasoning.encrypted_content`.
- Remove `supports_reasoning_summaries` from model metadata and retire the `model_supports_reasoning_summaries` configuration override.
- Use configured or model-default reasoning effort without a capability gate, including for guardian reviews and tracing.

GitOrigin-RevId: 2c9f194a5d2d4d688a2235299e6358f82ab8e1ea

codex-rs/core/src/client.rs

@@ -804,25 +804,21 @@ impl ModelClient {
         model_info: &ModelInfo,
         effort: Option<ReasoningEffortConfig>,
         summary: ReasoningSummaryConfig,
-    ) -> Option<Reasoning> {
-        if model_info.supports_reasoning_summaries {
-            Some(Reasoning {
-                effort: effort
-                    .or_else(|| model_info.default_reasoning_level.clone())
-                    .map(reasoning_effort_for_request),
-                summary: if summary == ReasoningSummaryConfig::None {
-                    None
-                } else {
-                    Some(summary)
-                },
-                // When Responses Lite is disabled, omit context so Responses uses the default,
-                // which is currently `current_turn`.
-                context: model_info
-                    .use_responses_lite
-                    .then_some(ReasoningContext::AllTurns),
-            })
-        } else {
-            None
+    ) -> Reasoning {
+        Reasoning {
+            effort: effort
+                .or_else(|| model_info.default_reasoning_level.clone())
+                .map(reasoning_effort_for_request),
+            summary: if summary == ReasoningSummaryConfig::None {
+                None
+            } else {
+                Some(summary)
+            },
+            // When Responses Lite is disabled, omit context so Responses uses the default,
+            // which is currently `current_turn`.
+            context: model_info
+                .use_responses_lite
+                .then_some(ReasoningContext::AllTurns),
         }
     }
 
@@ -871,12 +867,8 @@ impl ModelClient {
             .then_some(StreamOptions {
                 reasoning_summary_delivery: codex_api::ReasoningSummaryDelivery::SequentialCutoff,
             });
-        let reasoning = Self::build_reasoning(model_info, effort, summary);
-        let include = if reasoning.is_some() {
-            vec!["reasoning.encrypted_content".to_string()]
-        } else {
-            Vec::new()
-        };
+        let reasoning = Some(Self::build_reasoning(model_info, effort, summary));
+        let include = vec!["reasoning.encrypted_content".to_string()];
         let verbosity = if model_info.support_verbosity {
             self.state.model_verbosity.or(model_info.default_verbosity)
         } else {

codex-rs/core/src/client_tests.rs

@@ -262,7 +262,6 @@ fn test_model_info() -> ModelInfo {
         "upgrade": null,
         "base_instructions": "base instructions",
         "model_messages": null,
-        "supports_reasoning_summaries": false,
         "support_verbosity": false,
         "default_verbosity": null,
         "apply_patch_tool_type": null,

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

@@ -952,9 +952,6 @@ pub struct Config {
     /// using the Responses API. When unset, the model catalog default is used.
     pub model_reasoning_summary: Option<ReasoningSummary>,
 
-    /// Optional override to force-enable reasoning summaries for the configured model.
-    pub model_supports_reasoning_summaries: Option<bool>,
-
     /// Optional full model catalog loaded from `model_catalog_json`.
     /// When set, this replaces the bundled catalog for the current process.
     pub model_catalog: Option<ModelsResponse>,
@@ -1476,7 +1473,6 @@ impl Config {
             tool_output_token_limit: self.tool_output_token_limit,
             base_instructions: self.base_instructions.clone(),
             personality_enabled: self.features.enabled(Feature::Personality),
-            model_supports_reasoning_summaries: self.model_supports_reasoning_summaries,
             model_catalog: self.model_catalog.clone(),
         }
     }
@@ -3903,7 +3899,6 @@ impl Config {
             model_reasoning_effort: cfg.model_reasoning_effort,
             plan_mode_reasoning_effort: cfg.plan_mode_reasoning_effort,
             model_reasoning_summary: cfg.model_reasoning_summary,
-            model_supports_reasoning_summaries: cfg.model_supports_reasoning_summaries,
             model_catalog,
             model_verbosity: cfg.model_verbosity,
             chatgpt_base_url: cfg

codex-rs/core/src/guardian/review_session.rs

@@ -720,14 +720,10 @@ async fn run_review_on_session(
             &params.spawn_config.to_models_manager_config(),
         )
         .await;
-    let guardian_reasoning_effort = if model_info.supports_reasoning_summaries {
-        params
-            .reasoning_effort
-            .clone()
-            .or_else(|| model_info.default_reasoning_level.clone())
-    } else {
-        None
-    };
+    let guardian_reasoning_effort = params
+        .reasoning_effort
+        .clone()
+        .or_else(|| model_info.default_reasoning_level.clone());
     let mut analytics_result =
         GuardianReviewAnalyticsResult::from_session(GuardianReviewSessionAnalyticsParams {
             guardian_thread_id: review_session.codex.session.thread_id.to_string(),

codex-rs/core/src/session/turn_context.rs

@@ -177,13 +177,9 @@ impl TurnContext {
     }
 
     pub(crate) fn effective_reasoning_effort(&self) -> Option<ReasoningEffortConfig> {
-        if self.model_info.supports_reasoning_summaries {
-            self.reasoning_effort
-                .clone()
-                .or_else(|| self.model_info.default_reasoning_level.clone())
-        } else {
-            None
-        }
+        self.reasoning_effort
+            .clone()
+            .or_else(|| self.model_info.default_reasoning_level.clone())
     }
 
     pub(crate) fn effective_reasoning_effort_for_tracing(&self) -> String {