Fix provider context budgeting and ChatGPT subscription limits

app/src/ai/blocklist/controller.rs

@@ -81,11 +81,11 @@ use crate::ai::provider::ProviderConfig;
 #[cfg(not(target_family = "wasm"))]
 use crate::ai::remote_logging::{self, RemoteLogLevel, RemoteLogRecord};
 use crate::ai::runtime::{
-    prepare_provider_run, provider_runtime_for_request, OrchestrationModelOption,
-    PreparedProviderRun, ProviderActionContext, ProviderRunBlock, ProviderRunCoordinator,
-    ProviderRunProfile, ProviderRunProjection, ProviderRunResponseProjector,
-    ProviderToolExecutionRef, ProviderToolLifecycleOutcome, RuntimeResponseConfig,
-    BASE_PROVIDER_PROFILE, CLI_MONITOR_PROVIDER_PROFILE,
+    prepare_provider_run, provider_context_window_tokens, provider_runtime_for_request,
+    OrchestrationModelOption, PreparedProviderRun, ProviderActionContext, ProviderRunBlock,
+    ProviderRunCoordinator, ProviderRunProfile, ProviderRunProjection,
+    ProviderRunResponseProjector, ProviderToolExecutionRef, ProviderToolLifecycleOutcome,
+    RuntimeResponseConfig, BASE_PROVIDER_PROFILE, CLI_MONITOR_PROVIDER_PROFILE,
 };
 use crate::ai::AIRequestUsageModel;
 use crate::cloud_object::model::persistence::CloudModel;
@@ -112,7 +112,7 @@ use crate::workspaces::user_workspaces::UserWorkspaces;
 
 const PROGRESSIVE_SUMMARY_TRIGGER_USAGE: f32 = 0.70;
 const PROGRESSIVE_SUMMARY_RETAINED_USAGE: f32 = 0.50;
-const PROGRESSIVE_SUMMARY_MIN_RECENT_MESSAGES: usize = 20;
+const PROGRESSIVE_SUMMARY_MIN_RECENT_MESSAGES: usize = 1;
 const PROGRESSIVE_SUMMARY_OUTPUT_TOKENS: u32 = 8_000;
 const PROGRESSIVE_SUMMARY_CONTEXT_SAFETY_TOKENS: u32 = 2_000;
 const PROGRESSIVE_SUMMARY_START_TIMEOUT: Duration = Duration::from_secs(120);
@@ -199,7 +199,7 @@ fn progressive_summary_candidate(
 }
 
 fn estimated_text_tokens(text: &str) -> u32 {
-    u32::try_from(text.chars().count().div_ceil(4)).unwrap_or(u32::MAX)
+    u32::try_from(text.len().div_ceil(3)).unwrap_or(u32::MAX)
 }
 
 fn estimated_message_tokens(message: &ConversationMessage) -> u32 {
@@ -259,6 +259,8 @@ fn progressive_summary_split_point(
     for index in (0..messages.len()).rev() {
         let message_tokens = estimated_message_tokens(&messages[index]);
         let retained_count = messages.len() - index;
+        // Keep the latest message, then retain only as much history as fits.
+        // A fixed message-count floor can retain many oversized file reads.
         if retained_count > PROGRESSIVE_SUMMARY_MIN_RECENT_MESSAGES
             && retained_tokens.saturating_add(message_tokens) > retained_token_budget
         {
@@ -278,6 +280,17 @@ fn progressive_summary_split_point(
         split_point -= 1;
     }
 
+    // A single large tool batch can exceed the entire retained budget. Summarize
+    // the complete batch rather than keeping an oversized call/result pair forever.
+    // Its original results remain available in the tool-result archive.
+    if messages
+        .last()
+        .is_some_and(|message| content_contains_tool_result(&message.content))
+        && estimated_history_tokens(&messages[split_point..]) > retained_token_budget
+    {
+        return messages.len();
+    }
+
     split_point
 }
 
@@ -5678,13 +5691,19 @@ impl BlocklistAIController {
             self.fail_restored_provider_run(conversation_id, error, ctx);
             return;
         }
+        let base_provider_config =
+            ResponseStream::resolve_provider_config(snapshot.base_request.model.as_str(), ctx);
+        // A restored checkpoint may contain an older, larger catalog budget.
+        // Reconcile it before any resumed model call and persist the corrected limit.
+        snapshot.response_config.max_context_tokens = provider_context_window_tokens(
+            &base_provider_config,
+            snapshot.base_request.model.as_str(),
+            snapshot.response_config.max_context_tokens,
+        );
         if let Err(error) = self.persist_provider_run_snapshot(conversation_id, &snapshot, ctx) {
             self.fail_restored_provider_run(conversation_id, error, ctx);
             return;
         }
-
-        let base_provider_config =
-            ResponseStream::resolve_provider_config(snapshot.base_request.model.as_str(), ctx);
         let cli_provider_config = snapshot
             .cli_monitor_request
             .as_ref()
@@ -6583,6 +6602,7 @@ impl BlocklistAIController {
     fn begin_active_provider_progressive_summary(
         &mut self,
         conversation_id: AIConversationId,
+        force: bool,
         ctx: &mut ModelContext<Self>,
     ) -> bool {
         if self
@@ -6623,28 +6643,38 @@ impl BlocklistAIController {
                 return false;
             };
             (
-                conversation
-                    .current_context_tokens()
-                    .min(active_context_limit),
+                conversation.current_context_tokens(),
                 conversation.has_pending_progressive_summary(),
             )
         };
+        let transcript = active_run.coordinator.run().transcript();
+        let (estimated_context_tokens, persistent_context_tokens) = active_run
+            .coordinator
+            .estimated_context_tokens()
+            .unwrap_or_else(|| {
+                (
+                    current_context_tokens,
+                    current_context_tokens.saturating_sub(estimated_history_tokens(transcript)),
+                )
+            });
+        let current_context_tokens = current_context_tokens.max(estimated_context_tokens);
+        // Trigger and retain against the space history can actually use. Fixed
+        // prompts and a large output reservation cannot be reduced by summarizing.
+        let history_capacity = active_context_limit.saturating_sub(persistent_context_tokens);
+        let current_history_tokens =
+            current_context_tokens.saturating_sub(persistent_context_tokens);
         if summary_pending
             || last_failure_context_tokens == Some(current_context_tokens)
-            || current_context_tokens as f32 / (active_context_limit as f32)
-                < PROGRESSIVE_SUMMARY_TRIGGER_USAGE
+            || (!force
+                && current_history_tokens as f32 / (history_capacity.max(1) as f32)
+                    < PROGRESSIVE_SUMMARY_TRIGGER_USAGE)
         {
             return false;
         }
-
-        let transcript = active_run.coordinator.run().transcript();
-        let transcript_tokens = estimated_history_tokens(transcript);
-        let persistent_context_tokens = current_context_tokens.saturating_sub(transcript_tokens);
-        let retained_total_budget =
-            (active_context_limit as f32 * PROGRESSIVE_SUMMARY_RETAINED_USAGE) as u32;
-        let retained_history_budget = retained_total_budget
-            .saturating_sub(persistent_context_tokens)
-            .saturating_sub(PROGRESSIVE_SUMMARY_OUTPUT_TOKENS);
+        let retained_history_budget =
+            (history_capacity as f32 * PROGRESSIVE_SUMMARY_RETAINED_USAGE) as u32;
+        let retained_history_budget =
+            retained_history_budget.saturating_sub(PROGRESSIVE_SUMMARY_OUTPUT_TOKENS);
         let split_point = progressive_summary_split_point(transcript, retained_history_budget);
         if split_point == 0 {
             return false;
@@ -6851,6 +6881,16 @@ impl BlocklistAIController {
         let mut summary_applied = false;
         let mut recorded_usage = None;
         match result {
+            Ok((summary, usage, summarizer_model_id))
+                if estimated_history_tokens(&progressive_summary_messages(summary.clone()))
+                    >= estimated_history_tokens(&plan.summarized_prefix) =>
+            {
+                log::warn!(
+                    "[progressive-summary] Summary did not reduce context for conversation {:?}",
+                    conversation_id,
+                );
+                recorded_usage = Some((usage, summarizer_model_id));
+            }
             Ok((summary, usage, summarizer_model_id)) => {
                 let Some(run) = self
                     .active_provider_runs
@@ -6925,10 +6965,6 @@ impl BlocklistAIController {
             }
         }
 
-        let failure_context_tokens = BlocklistAIHistoryModel::as_ref(ctx)
-            .conversation(&conversation_id)
-            .map(AIConversation::current_context_tokens)
-            .unwrap_or(plan.trigger_context_tokens);
         if let Some(run) = self
             .active_provider_runs
             .get_mut(&conversation_id)
@@ -6938,7 +6974,7 @@ impl BlocklistAIController {
                 None
             } else {
                 // Fail open and suppress another request at this unchanged context boundary.
-                Some(failure_context_tokens)
+                Some(plan.trigger_context_tokens)
             };
         }
         if let Some((usage, summarizer_model_id)) = recorded_usage {
@@ -6998,7 +7034,7 @@ impl BlocklistAIController {
         if self.apply_ready_active_provider_progressive_summary(conversation_id, ctx) {
             return;
         }
-        self.begin_active_provider_progressive_summary(conversation_id, ctx);
+        self.begin_active_provider_progressive_summary(conversation_id, false, ctx);
         if matches!(
             self.active_provider_progressive_summaries
                 .get(&conversation_id),
@@ -7471,7 +7507,7 @@ impl BlocklistAIController {
                     );
                     return;
                 }
-                if !self.begin_active_provider_progressive_summary(conversation_id, ctx) {
+                if !self.begin_active_provider_progressive_summary(conversation_id, true, ctx) {
                     self.fail_active_provider_run(
                         conversation_id,
                         "provider context overflow could not start compaction".to_string(),

app/src/ai/blocklist/controller_tests.rs

@@ -3734,3 +3734,81 @@ fn optimistic_cli_subagent_completion_with_in_flight_stream_reports_success() {
         });
     });
 }
+
+#[test]
+fn progressive_summary_compacts_short_histories_to_the_token_budget() {
+    let messages = vec![
+        ConversationMessage {
+            role: MessageRole::User,
+            content: MessageContent::Text("large project context".repeat(1_000)),
+        },
+        ConversationMessage {
+            role: MessageRole::Assistant,
+            content: MessageContent::Text("Working on the requested change".to_string()),
+        },
+        ConversationMessage {
+            role: MessageRole::User,
+            content: MessageContent::Text("Please continue".to_string()),
+        },
+    ];
+    assert_eq!(super::progressive_summary_split_point(&messages, 100), 1);
+}
+
+#[test]
+fn progressive_summary_includes_an_oversized_final_tool_batch() {
+    let messages = vec![
+        ConversationMessage {
+            role: MessageRole::Assistant,
+            content: MessageContent::ToolUse {
+                tool_use_id: "read".to_string(),
+                name: "read_file".to_string(),
+                input: serde_json::json!({"path": "large.rs"}),
+            },
+        },
+        ConversationMessage {
+            role: MessageRole::User,
+            content: MessageContent::ToolResult {
+                tool_use_id: "read".to_string(),
+                content: "file contents".repeat(1_000),
+                is_error: false,
+            },
+        },
+    ];
+    assert_eq!(super::progressive_summary_split_point(&messages, 100), 2);
+    assert_eq!(
+        super::progressive_summary_split_point(&messages, 100_000),
+        0
+    );
+}
+
+#[test]
+fn progressive_summary_keeps_retained_tool_results_paired() {
+    let messages = vec![
+        ConversationMessage {
+            role: MessageRole::User,
+            content: MessageContent::Text("old project context".repeat(1_000)),
+        },
+        ConversationMessage {
+            role: MessageRole::Assistant,
+            content: MessageContent::ToolUse {
+                tool_use_id: "read".to_string(),
+                name: "read_file".to_string(),
+                input: serde_json::json!({"path": "small.rs"}),
+            },
+        },
+        ConversationMessage {
+            role: MessageRole::User,
+            content: MessageContent::ToolResult {
+                tool_use_id: "read".to_string(),
+                content: "file contents".to_string(),
+                is_error: false,
+            },
+        },
+        ConversationMessage {
+            role: MessageRole::Assistant,
+            content: MessageContent::Text("I found the issue".to_string()),
+        },
+    ];
+    let budget = super::estimated_history_tokens(&messages[2..]);
+    assert_eq!(super::progressive_summary_split_point(&messages, budget), 1);
+}

app/src/ai/llms.rs

@@ -2630,17 +2630,20 @@ fn get_new_agent_mode_choices(
 
 #[cfg(not(target_family = "wasm"))]
 fn openai_model_context_size(model: &OpenAIModelConfig, provider_kind: OpenAIProviderKind) -> u32 {
-    // Older saved ChatGPT catalogs stored the default window in max_input_tokens.
-    // Preserve their larger usable window until the catalog refresh separates them.
-    if provider_kind == OpenAIProviderKind::ChatGPTSubscription
-        && model.default_context_size.is_none()
-    {
-        return model.context_size;
-    }
-    model
+    let input_limit = model
         .max_input_tokens
         .unwrap_or(model.context_size)
-        .min(model.context_size)
+        .min(model.context_size);
+    if provider_kind == OpenAIProviderKind::ChatGPTSubscription {
+        // The catalog's default window is the supported session budget. The
+        // advertised maximum must not silently opt subscriptions into long context.
+        // Older saved catalogs kept the default in max_input_tokens instead.
+        return model
+            .default_context_size
+            .unwrap_or(input_limit)
+            .min(input_limit);
+    }
+    input_limit
 }
 
 /// Merges endpoint metadata into a provider's configured models without
@@ -2749,8 +2752,7 @@ fn openai_model_context_window(
         is_configurable: max_context_size > default_context_size,
         min: default_context_size,
         max: max_context_size,
-        // Use the full usable window; the catalog default remains available as
-        // the smaller configurable budget, not as a hard input ceiling.
+        // Subscription limits are already capped to the catalog's default above.
         default_max: max_context_size,
     }
 }

app/src/ai/llms_tests.rs

@@ -818,10 +818,10 @@ fn chatgpt_codex_models_parse_visible_catalog_entries() {
         &models[0],
         crate::settings::OpenAIProviderKind::ChatGPTSubscription,
     );
-    assert!(configurable.is_configurable);
+    assert!(!configurable.is_configurable);
     assert_eq!(configurable.min, 258_400);
-    assert_eq!(configurable.default_max, 828_400);
-    assert_eq!(configurable.max, 828_400);
+    assert_eq!(configurable.default_max, 258_400);
+    assert_eq!(configurable.max, 258_400);
 
     let fixed =
         openai_model_context_window(&models[0], crate::settings::OpenAIProviderKind::LiteLLM);
@@ -883,7 +883,7 @@ fn provider_context_budget_respects_hard_input_and_total_limits() {
     model.max_input_tokens = Some(400_000);
     let window = openai_model_context_window(&model, OpenAIProviderKind::ChatGPTSubscription);
     assert_eq!(window.min, 272_000);
-    assert_eq!(window.max, 400_000);
+    assert_eq!(window.max, 272_000);
     assert_eq!(
         openai_model_context_size(&model, OpenAIProviderKind::ChatGPTSubscription),
         window.max
@@ -891,13 +891,15 @@ fn provider_context_budget_respects_hard_input_and_total_limits() {
 }
 
 #[test]
-fn legacy_chatgpt_default_does_not_limit_routing() {
+fn legacy_chatgpt_default_limits_routing() {
     let mut model = openai_model("legacy-model");
     model.context_size = 872_000;
     model.max_input_tokens = Some(272_000);
     let window = openai_model_context_window(&model, OpenAIProviderKind::ChatGPTSubscription);
     assert_eq!(window.min, 272_000);
-    assert_eq!(window.max, 872_000);
+    assert_eq!(window.max, 272_000);
+    assert_eq!(window.default_max, 272_000);
+    assert!(!window.is_configurable);
     assert_eq!(
         openai_model_context_size(&model, OpenAIProviderKind::ChatGPTSubscription),
         window.max
@@ -944,3 +946,19 @@ fn provider_registry_overrides_legacy_endpoint_for_duplicate_models() {
         assert_eq!(config.api_key.as_deref(), Some("current-key"));
     });
 }
+
+#[test]
+fn chatgpt_default_window_limits_routing_without_a_separate_input_limit() {
+    let mut model = openai_model("subscription-model");
+    model.context_size = 872_000;
+    model.default_context_size = Some(272_000);
+    model.max_input_tokens = None;
+    let window = openai_model_context_window(&model, OpenAIProviderKind::ChatGPTSubscription);
+    assert_eq!(window.default_max, 272_000);
+    assert_eq!(window.max, 272_000);
+    assert!(!window.is_configurable);
+    assert_eq!(
+        openai_model_context_size(&model, OpenAIProviderKind::ChatGPTSubscription),
+        272_000
+    );
+}

app/src/ai/runtime/mod.rs

@@ -13,6 +13,7 @@ pub(crate) use provider_run_coordinator::{
     CLI_MONITOR_PROVIDER_PROFILE,
 };
 pub(crate) use rig::{
-    prepare_provider_run, provider_runtime_for_request, PreparedProviderRun, ProviderActionContext,
+    prepare_provider_run, provider_context_window_tokens, provider_runtime_for_request,
+    PreparedProviderRun, ProviderActionContext,
 };
 pub(crate) use rig_request::OrchestrationModelOption;

app/src/ai/runtime/provider_run_coordinator.rs

@@ -244,6 +244,21 @@ impl ProviderRunCoordinator {
         self.profiles.get(profile).map(|profile| &profile.request)
     }
 
+    /// Includes the current transcript, fixed request context, tools, and output reservation.
+    /// Read at the model boundary so newly committed tool output is included.
+    pub(crate) fn estimated_context_tokens(&self) -> Option<(u32, u32)> {
+        let profile = self.profiles.get(self.run.profile().as_str())?;
+        let mut request = profile.request.clone();
+        request.prompt = None;
+        request.messages.clear();
+        let persistent_tokens = estimate_turn_request_tokens(&request);
+        request.messages = self.run.transcript().to_vec();
+        Some((
+            u32::try_from(estimate_turn_request_tokens(&request)).unwrap_or(u32::MAX),
+            u32::try_from(persistent_tokens).unwrap_or(u32::MAX),
+        ))
+    }
+
     pub(crate) fn set_max_context_tokens(&mut self, max_context_tokens: Option<u32>) {
         self.max_context_tokens = max_context_tokens;
     }
@@ -453,7 +468,10 @@ impl ProviderRunCoordinator {
             return false;
         };
         let request = request_for_model_call(profile.request.clone(), call);
-        estimate_turn_request_tokens(&request) >= u64::from(max_context_tokens)
+        // Provider tokenizers and request envelopes differ. Compact before the
+        // estimate reaches the advertised limit, leaving room for that uncertainty.
+        let safe_context_tokens = u64::from(max_context_tokens) * 9 / 10;
+        estimate_turn_request_tokens(&request) >= safe_context_tokens
     }
 
     async fn checkpoint_or_fail<C>(
@@ -1120,42 +1138,33 @@ fn request_for_model_call(mut template: TurnRequest, call: &ProviderModelCall) -
     template
 }
 
-const ESTIMATED_CHARS_PER_TOKEN: u64 = 4;
+const ESTIMATED_BYTES_PER_TOKEN: u64 = 3;
+const ESTIMATED_REQUEST_OVERHEAD_TOKENS: u64 = 512;
 
-/// Deliberately overestimates request size without requiring provider-specific tokenizers.
+/// Conservative estimate, not an exact tokenizer count. UTF-8 bytes account for
+/// non-ASCII content better than character counts; the caller also leaves headroom.
 fn estimate_turn_request_tokens(request: &TurnRequest) -> u64 {
-    let mut chars = request
+    let mut bytes = request
         .system_prompt
         .as_deref()
-        .map_or(0, |text| text.chars().count());
-    chars += request.prompt.as_ref().map_or(0, |prompt| {
-        serde_json::to_string(prompt)
-            .unwrap_or_default()
-            .chars()
-            .count()
+        .map_or(0, |text| text.len());
+    bytes += request.prompt.as_ref().map_or(0, |prompt| {
+        serde_json::to_string(prompt).unwrap_or_default().len()
     });
-    chars += request
+    bytes += request
         .messages
         .iter()
-        .map(|message| {
-            serde_json::to_string(message)
-                .unwrap_or_default()
-                .chars()
-                .count()
-        })
+        .map(|message| serde_json::to_string(message).unwrap_or_default().len())
         .sum::<usize>();
-    chars += request
+    bytes += request
         .tools
         .iter()
-        .map(|tool| {
-            serde_json::to_string(tool)
-                .unwrap_or_default()
-                .chars()
-                .count()
-        })
+        .map(|tool| serde_json::to_string(tool).unwrap_or_default().len())
         .sum::<usize>();
-    let input_tokens = (chars as u64).div_ceil(ESTIMATED_CHARS_PER_TOKEN);
-    input_tokens.saturating_add(request.max_output_tokens.unwrap_or_default())
+    let input_tokens = (bytes as u64).div_ceil(ESTIMATED_BYTES_PER_TOKEN);
+    input_tokens
+        .saturating_add(ESTIMATED_REQUEST_OVERHEAD_TOKENS)
+        .saturating_add(request.max_output_tokens.unwrap_or_default())
 }
 
 fn tool_event_call_id(event: &ToolEvent) -> Result<&str, ProviderRunCoordinatorError> {

app/src/ai/runtime/provider_run_coordinator_tests.rs

@@ -186,7 +186,7 @@ fn estimates_turn_request_with_system_tools_messages_and_output() {
         + serde_json::to_string(&request.tools[0]).unwrap().len()) as u64;
     assert_eq!(
         estimate_turn_request_tokens(&request),
-        expected_input.div_ceil(ESTIMATED_CHARS_PER_TOKEN) + 10
+        expected_input.div_ceil(ESTIMATED_BYTES_PER_TOKEN) + ESTIMATED_REQUEST_OVERHEAD_TOKENS + 10
     );
 }
 
@@ -1370,3 +1370,58 @@ fn session_runtime_is_rejected_before_any_turn_can_start() {
         ProviderRunCoordinatorError::InvalidRuntime(_)
     ));
 }
+
+#[test]
+fn context_estimate_tracks_live_transcript_and_reserves_fixed_context() {
+    let runtime = Arc::new(ScriptedRuntime::new(vec![]));
+    let mut request = request();
+    request.system_prompt = Some("project instructions".repeat(100));
+    request.max_output_tokens = Some(4_000);
+    let mut coordinator = ProviderRunCoordinator::from_request(
+        "context-budget",
+        runtime,
+        request,
+        Vec::new(),
+        ProviderRunLimits::default(),
+    )
+    .unwrap();
+    let (before, fixed_before) = coordinator.estimated_context_tokens().unwrap();
+    assert!(fixed_before > 4_000);
+    coordinator
+        .run_mut()
+        .compact_transcript_at_model_boundary(
+            1,
+            vec![ConversationMessage {
+                role: MessageRole::User,
+                content: MessageContent::Text("new large tool output".repeat(1_000)),
+            }],
+        )
+        .unwrap();
+    let (after, fixed_after) = coordinator.estimated_context_tokens().unwrap();
+    assert!(after > before + 4_000);
+    assert_eq!(fixed_before, fixed_after);
+}
+
+#[tokio::test]
+async fn preflight_leaves_headroom_before_the_advertised_context_limit() {
+    let runtime = Arc::new(ScriptedRuntime::new(vec![answer_turn()]));
+    let mut coordinator = coordinator(runtime.clone());
+    let (estimated_tokens, _) = coordinator.estimated_context_tokens().unwrap();
+    coordinator.set_max_context_tokens(Some(estimated_tokens + 1));
+    let (_sender, control) = turn_control();
+    let block = coordinator
+        .drive_until_blocked(control, |_| Ok(()))
+        .await
+        .unwrap();
+    assert_eq!(block, ProviderRunBlock::ContextWindowExceeded);
+    assert!(runtime.requests().is_empty());
+}
+
+#[test]
+fn request_estimate_accounts_for_multibyte_text() {
+    let mut request = request();
+    request.system_prompt = Some("a".repeat(1_000));
+    let ascii_tokens = estimate_turn_request_tokens(&request);
+    request.system_prompt = Some("界".repeat(1_000));
+    assert!(estimate_turn_request_tokens(&request) > ascii_tokens + 600);
+}

app/src/ai/runtime/rig.rs

@@ -293,18 +293,22 @@ fn bedrock_max_output_tokens(model: &str) -> u64 {
         .unwrap_or(64_000)
 }
 
-fn provider_context_window_tokens(
+pub(crate) fn provider_context_window_tokens(
     provider_config: &crate::ai::provider::ProviderConfig,
     model: &str,
     configured_limit: Option<u32>,
 ) -> Option<u32> {
-    configured_limit.or_else(|| match provider_config {
+    let provider_limit = match provider_config {
         crate::ai::provider::ProviderConfig::Bedrock(_) => {
             model_metadata(model).and_then(|metadata| metadata.context_window_tokens)
         }
-        crate::ai::provider::ProviderConfig::OpenAI(_)
-        | crate::ai::provider::ProviderConfig::None => None,
-    })
+        crate::ai::provider::ProviderConfig::OpenAI(config) => config.max_input_tokens,
+        crate::ai::provider::ProviderConfig::None => None,
+    };
+    match (configured_limit, provider_limit) {
+        (Some(configured), Some(provider)) => Some(configured.min(provider)),
+        (configured, provider) => configured.or(provider),
+    }
 }
 
 #[cfg(test)]

app/src/ai/runtime/rig_tests.rs

@@ -55,3 +55,21 @@ async fn missing_cli_provider_route_falls_back_to_base_provider_profile() {
         .iter()
         .any(|tool| tool.name == "read_shell_command_output"));
 }
+
+#[test]
+fn subscription_context_budget_uses_catalog_limit_and_clamps_stale_overrides() {
+    let mut config = openai_config("subscription-model");
+    config.kind = OpenAIProviderKind::ChatGPTSubscription;
+    config.max_input_tokens = Some(272_000);
+    let provider = ProviderConfig::OpenAI(config);
+    for (selected, expected) in [
+        (None, 272_000),
+        (Some(872_000), 272_000),
+        (Some(128_000), 128_000),
+    ] {
+        assert_eq!(
+            super::provider_context_window_tokens(&provider, "subscription-model", selected),
+            Some(expected)
+        );
+    }
+}