persisting credits if new snapshot does not contain credit info (#7490)

in response to incoming changes to responses headers where the header
may sometimes not contain credits info (no longer forcing a credit
check)

codex-rs/core/src/codex.rs

@@ -2481,7 +2481,10 @@ mod tests {
     use crate::tools::format_exec_output_str;
 
     use crate::protocol::CompactedItem;
+    use crate::protocol::CreditsSnapshot;
     use crate::protocol::InitialHistory;
+    use crate::protocol::RateLimitSnapshot;
+    use crate::protocol::RateLimitWindow;
     use crate::protocol::ResumedHistory;
     use crate::state::TaskKind;
     use crate::tasks::SessionTask;
@@ -2551,6 +2554,75 @@ mod tests {
         assert_eq!(expected, actual);
     }
 
+    #[test]
+    fn set_rate_limits_retains_previous_credits() {
+        let codex_home = tempfile::tempdir().expect("create temp dir");
+        let config = Config::load_from_base_config_with_overrides(
+            ConfigToml::default(),
+            ConfigOverrides::default(),
+            codex_home.path().to_path_buf(),
+        )
+        .expect("load default test config");
+        let config = Arc::new(config);
+        let session_configuration = SessionConfiguration {
+            provider: config.model_provider.clone(),
+            model: config.model.clone(),
+            model_reasoning_effort: config.model_reasoning_effort,
+            model_reasoning_summary: config.model_reasoning_summary,
+            developer_instructions: config.developer_instructions.clone(),
+            user_instructions: config.user_instructions.clone(),
+            base_instructions: config.base_instructions.clone(),
+            compact_prompt: config.compact_prompt.clone(),
+            approval_policy: config.approval_policy,
+            sandbox_policy: config.sandbox_policy.clone(),
+            cwd: config.cwd.clone(),
+            original_config_do_not_use: Arc::clone(&config),
+            features: Features::default(),
+            exec_policy: Arc::new(ExecPolicy::empty()),
+            session_source: SessionSource::Exec,
+        };
+
+        let mut state = SessionState::new(session_configuration);
+        let initial = RateLimitSnapshot {
+            primary: Some(RateLimitWindow {
+                used_percent: 10.0,
+                window_minutes: Some(15),
+                resets_at: Some(1_700),
+            }),
+            secondary: None,
+            credits: Some(CreditsSnapshot {
+                has_credits: true,
+                unlimited: false,
+                balance: Some("10.00".to_string()),
+            }),
+        };
+        state.set_rate_limits(initial.clone());
+
+        let update = RateLimitSnapshot {
+            primary: Some(RateLimitWindow {
+                used_percent: 40.0,
+                window_minutes: Some(30),
+                resets_at: Some(1_800),
+            }),
+            secondary: Some(RateLimitWindow {
+                used_percent: 5.0,
+                window_minutes: Some(60),
+                resets_at: Some(1_900),
+            }),
+            credits: None,
+        };
+        state.set_rate_limits(update.clone());
+
+        assert_eq!(
+            state.latest_rate_limits,
+            Some(RateLimitSnapshot {
+                primary: update.primary.clone(),
+                secondary: update.secondary,
+                credits: initial.credits,
+            })
+        );
+    }
+
     #[test]
     fn prefers_structured_content_when_present() {
         let ctr = CallToolResult {

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

@@ -62,7 +62,10 @@ impl SessionState {
     }
 
     pub(crate) fn set_rate_limits(&mut self, snapshot: RateLimitSnapshot) {
-        self.latest_rate_limits = Some(snapshot);
+        self.latest_rate_limits = Some(merge_rate_limit_credits(
+            self.latest_rate_limits.as_ref(),
+            snapshot,
+        ));
     }
 
     pub(crate) fn token_info_and_rate_limits(
@@ -79,3 +82,14 @@ impl SessionState {
         self.history.get_total_token_usage()
     }
 }
+
+// Sometimes new snapshots don't include credits
+fn merge_rate_limit_credits(
+    previous: Option<&RateLimitSnapshot>,
+    mut snapshot: RateLimitSnapshot,
+) -> RateLimitSnapshot {
+    if snapshot.credits.is_none() {
+        snapshot.credits = previous.and_then(|prior| prior.credits.clone());
+    }
+    snapshot
+}

codex-rs/tui/src/chatwidget.rs

@@ -20,6 +20,7 @@ use codex_core::protocol::AgentReasoningRawContentDeltaEvent;
 use codex_core::protocol::AgentReasoningRawContentEvent;
 use codex_core::protocol::ApplyPatchApprovalRequestEvent;
 use codex_core::protocol::BackgroundEventEvent;
+use codex_core::protocol::CreditsSnapshot;
 use codex_core::protocol::DeprecationNoticeEvent;
 use codex_core::protocol::ErrorEvent;
 use codex_core::protocol::Event;
@@ -558,7 +559,19 @@ impl ChatWidget {
     }
 
     pub(crate) fn on_rate_limit_snapshot(&mut self, snapshot: Option<RateLimitSnapshot>) {
-        if let Some(snapshot) = snapshot {
+        if let Some(mut snapshot) = snapshot {
+            if snapshot.credits.is_none() {
+                snapshot.credits = self
+                    .rate_limit_snapshot
+                    .as_ref()
+                    .and_then(|display| display.credits.as_ref())
+                    .map(|credits| CreditsSnapshot {
+                        has_credits: credits.has_credits,
+                        unlimited: credits.unlimited,
+                        balance: credits.balance.clone(),
+                    });
+            }
+
             let warnings = self.rate_limit_warnings.take_warnings(
                 snapshot
                     .secondary

codex-rs/tui/src/chatwidget/tests.rs

@@ -18,6 +18,7 @@ use codex_core::protocol::AgentReasoningDeltaEvent;
 use codex_core::protocol::AgentReasoningEvent;
 use codex_core::protocol::ApplyPatchApprovalRequestEvent;
 use codex_core::protocol::BackgroundEventEvent;
+use codex_core::protocol::CreditsSnapshot;
 use codex_core::protocol::Event;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::ExecApprovalRequestEvent;
@@ -521,6 +522,53 @@ fn test_rate_limit_warnings_monthly() {
     );
 }
 
+#[test]
+fn rate_limit_snapshot_keeps_prior_credits_when_missing_from_headers() {
+    let (mut chat, _rx, _op_rx) = make_chatwidget_manual();
+
+    chat.on_rate_limit_snapshot(Some(RateLimitSnapshot {
+        primary: None,
+        secondary: None,
+        credits: Some(CreditsSnapshot {
+            has_credits: true,
+            unlimited: false,
+            balance: Some("17.5".to_string()),
+        }),
+    }));
+    let initial_balance = chat
+        .rate_limit_snapshot
+        .as_ref()
+        .and_then(|snapshot| snapshot.credits.as_ref())
+        .and_then(|credits| credits.balance.as_deref());
+    assert_eq!(initial_balance, Some("17.5"));
+
+    chat.on_rate_limit_snapshot(Some(RateLimitSnapshot {
+        primary: Some(RateLimitWindow {
+            used_percent: 80.0,
+            window_minutes: Some(60),
+            resets_at: Some(123),
+        }),
+        secondary: None,
+        credits: None,
+    }));
+
+    let display = chat
+        .rate_limit_snapshot
+        .as_ref()
+        .expect("rate limits should be cached");
+    let credits = display
+        .credits
+        .as_ref()
+        .expect("credits should persist when headers omit them");
+
+    assert_eq!(credits.balance.as_deref(), Some("17.5"));
+    assert!(!credits.unlimited);
+    assert_eq!(
+        display.primary.as_ref().map(|window| window.used_percent),
+        Some(80.0)
+    );
+}
+
 #[test]
 fn rate_limit_switch_prompt_skips_when_on_lower_cost_model() {
     let (mut chat, _, _) = make_chatwidget_manual();