Share the Guardian context delivery token limit (#58071)

Expose `MAX_TEXT_PART_ESTIMATED_TOKENS` from `codex-guardian-context` and use it for native tool calls, transcript entries, and delivery-size assertions. Keep the existing 9,000-token limit while replacing duplicated limits in code and tests.

GitOrigin-RevId: 90cb98eea9bade34f18db0d1666ed7ed1e93febe

codex-rs/core/tests/suite/guardian_context_budget.rs

@@ -10,6 +10,7 @@ use codex_core::config::RolloutBudgetConfig;
 use codex_core::context::GuardianContextMode;
 use codex_extension_api::ExtensionRegistryBuilder;
 use codex_features::Feature;
+use codex_guardian_context::MAX_TEXT_PART_ESTIMATED_TOKENS;
 use codex_history::RolloutItem;
 use codex_protocol::config_types::ApprovalsReviewer;
 use codex_protocol::models::ContentItem;
@@ -19,6 +20,7 @@ use codex_protocol::protocol::AskForApproval;
 use codex_protocol::protocol::EventMsg;
 use codex_protocol::protocol::Op;
 use codex_protocol::protocol::ReviewDecision;
+use codex_protocol::protocol::TruncationPolicy;
 use codex_protocol::user_input::UserInput;
 use core_test_support::ThreadIdle;
 use core_test_support::responses;
@@ -817,7 +819,8 @@ async fn oversized_action_preserves_review_policy_and_next_review(
         let parts = reviews[0].message_input_texts("user");
         let context = parts.concat();
         assert!(context.contains(&oversized_command));
-        assert!(parts.iter().all(|part| part.len() <= 36_000));
+        assert!(parts.iter().all(|part| part.len()
+            <= TruncationPolicy::Tokens(MAX_TEXT_PART_ESTIMATED_TOKENS).byte_budget()));
         let transcript = context
             .split_once(">>> TRANSCRIPT START\n")
             .expect("full transcript")

codex-rs/guardian-context/src/action.rs

@@ -4,6 +4,7 @@
 
 use crate::ContextSection;
 use crate::GuardianToolDescriptions;
+use crate::MAX_TEXT_PART_ESTIMATED_TOKENS;
 use crate::SectionContributor;
 use crate::SectionError;
 use crate::SectionInput;
@@ -181,7 +182,7 @@ impl SectionContributor for PlannedActionSection {
             });
         }
         if let PlannedActionKind::ToolCall(call) = &action.kind
-            && crate::native_tool_call::estimate_tokens(call) > 9_000
+            && crate::native_tool_call::estimate_tokens(call) > MAX_TEXT_PART_ESTIMATED_TOKENS
         {
             return Err(SectionError::EvidenceLimitExceeded {
                 section: "native_tool_call",

codex-rs/guardian-context/src/composition.rs

@@ -648,9 +648,9 @@ fn delivered_message(
     }
 }
 
-// Preserve the delivery cap below the 10K-token context-item guidance. The
-// estimate uses four bytes per token, so each UTF-8-safe part is at most 36KB.
-const MAX_TEXT_PART_ESTIMATED_TOKENS: usize = 9_000;
+/// Delivery cap below the 10K-token context-item guidance, also applied to native calls.
+/// The estimate uses four bytes per token, so each UTF-8-safe text part is at most 36KB.
+pub const MAX_TEXT_PART_ESTIMATED_TOKENS: usize = 9_000;
 
 /// Bounds individual text parts without changing source text or entry identity.
 /// Budget estimates include the extra wire framing before transport conversion.

codex-rs/guardian-context/src/composition_tests.rs

@@ -103,9 +103,8 @@ fn long_text_and_file_image_delivery_is_lossless_bounded_and_fully_budgeted() {
         .collect::<Vec<_>>();
     assert_eq!(parts.concat(), text);
     assert!(
-        parts
-            .iter()
-            .all(|part| part.len() <= TruncationPolicy::Tokens(9_000).byte_budget())
+        parts.iter().all(|part| part.len()
+            <= TruncationPolicy::Tokens(MAX_TEXT_PART_ESTIMATED_TOKENS).byte_budget())
     );
     assert!(estimated >= crate::estimate_input_tokens(&messages[0]));
     let mut expected_inputs = parts

codex-rs/guardian-context/src/lib.rs

@@ -96,6 +96,7 @@ pub use codex_protocol::TranscriptFormat;
 pub use composition::CollectedContext;
 pub use composition::ComposedContext;
 pub use composition::ContextPresentation;
+pub use composition::MAX_TEXT_PART_ESTIMATED_TOKENS;
 pub use composition::PreparedTranscript;
 pub use preparation::ContextProfile;
 pub use preparation::SyncImagePreparer;

codex-rs/guardian-context/src/transcript.rs

@@ -24,6 +24,7 @@ use codex_protocol::protocol::InterAgentCommunication;
 use crate::ContextSection;
 use crate::ConversationTranscriptEntry;
 use crate::ConversationTranscriptEntryKind;
+use crate::MAX_TEXT_PART_ESTIMATED_TOKENS;
 use crate::PlannedAction;
 use crate::PlannedActionKind;
 use crate::SectionContributor;
@@ -322,7 +323,10 @@ fn collect_transcript_for_review(
                     entries.push(ConversationTranscriptEntry {
                         kind,
                         content: if crate::estimate_input_tokens(item)
-                            <= config.entry_limits.tool_tokens.min(9_000)
+                            <= config
+                                .entry_limits
+                                .tool_tokens
+                                .min(MAX_TEXT_PART_ESTIMATED_TOKENS)
                         {
                             TranscriptContent::NativeMessage(Box::new(item.clone()))
                         } else {