diff --git a/backend/crates/providers/openai/src/transport/privacy/carrier.rs b/backend/crates/providers/openai/src/transport/privacy/carrier.rs
index c42d8021e..98b3efeb6 100644
--- a/backend/crates/providers/openai/src/transport/privacy/carrier.rs
+++ b/backend/crates/providers/openai/src/transport/privacy/carrier.rs
@@ -4,15 +4,17 @@ use gateway_core::settings::privacy::PrivacyScope;
 use reqwest::header::{HeaderMap, HeaderValue};
 use serde_json::Value;
 
-use super::{Budget, rule::CompiledRule};
+use super::{Budget, changes::BodyChanges, rule::CompiledRule};
 
 const METADATA_KEYS: &[&str] = &["turnMetadata", "turn_metadata", "x-codex-turn-metadata"];
 
-pub(super) fn apply(
+pub(super) fn prepare(
     rule: &CompiledRule,
-    body: &mut Value,
+    body: &Value,
     headers: &mut HeaderMap,
     turn_metadata: &mut Option<String>,
+    changes: &mut BodyChanges,
+    contexts: &mut ContextIndex,
     budget: &mut Budget<'_>,
 ) -> Result<usize, &'static str> {
     match rule.rule.scope {
@@ -30,16 +32,15 @@ pub(super) fn apply(
                     *value = HeaderValue::from_str(&raw).map_err(|_| "metadata 请求头编码无效")?;
                 }
             }
-            count += metadata_fields(rule, body, budget)?;
-            if let Some(client) = body.get_mut("client_metadata") {
-                count += metadata_fields(rule, client, budget)?;
-            }
+            count += metadata_fields(rule, body, changes, budget)?;
             Ok(count)
         }
         PrivacyScope::DesktopGitContext | PrivacyScope::EnvironmentText => {
-            contexts(rule, body, budget)
+            contexts.apply(rule, body, changes, budget)
+        }
+        PrivacyScope::RequestBody => {
+            changes.stage(body, "", budget, |next, budget| rule.apply(next, budget))
         }
-        PrivacyScope::RequestBody => rule.apply(body, budget),
         PrivacyScope::RequestHeader => {
             let name = reqwest::header::HeaderName::from_bytes(rule.rule.selector.as_bytes())
                 .map_err(|_| "请求头名称无效")?;
@@ -83,17 +84,22 @@ pub(super) fn apply(
 
 fn metadata_fields(
     rule: &CompiledRule,
-    object: &mut Value,
+    body: &Value,
+    changes: &mut BodyChanges,
     budget: &mut Budget<'_>,
 ) -> Result<usize, &'static str> {
     let mut count = 0;
-    for key in METADATA_KEYS {
-        if let Some(value) = object.get_mut(*key) {
-            match value {
-                Value::String(raw) => count += metadata(rule, raw, budget)?,
-                Value::Object(_) => count += rule.apply(value, budget)?,
-                _ => return Err("metadata 必须是 JSON 对象或编码后的字符串"),
+    for prefix in ["", "/client_metadata"] {
+        for key in METADATA_KEYS {
+            let path = format!("{prefix}/{key}");
+            if body.pointer(&path).is_none() {
+                continue;
             }
+            count += changes.stage(body, &path, budget, |next, budget| match next {
+                Value::String(raw) => metadata(rule, raw, budget),
+                Value::Object(_) => rule.apply(next, budget),
+                _ => Err("metadata 必须是 JSON 对象或编码后的字符串"),
+            })?;
         }
     }
     Ok(count)
@@ -121,74 +127,130 @@ fn metadata(
     Ok(count)
 }
 
-fn contexts(
-    rule: &CompiledRule,
-    body: &mut Value,
-    budget: &mut Budget<'_>,
-) -> Result<usize, &'static str> {
-    let Some(items) = body.get_mut("input").and_then(Value::as_array_mut) else {
-        return Ok(0);
-    };
-    let mut count = 0;
-    for item in items {
-        budget.step()?;
-        let role = item
-            .get("role")
-            .and_then(Value::as_str)
-            .unwrap_or("")
-            .to_owned();
+#[derive(Default)]
+pub(super) struct ContextIndex {
+    desktop: Option<Vec<ContextTarget>>,
+    environment: Option<Vec<ContextTarget>>,
+}
+
+struct ContextTarget {
+    path: String,
+    open: &'static str,
+    close: &'static str,
+    identified: bool,
+}
+
+impl ContextIndex {
+    fn apply(
+        &mut self,
+        rule: &CompiledRule,
+        body: &Value,
+        changes: &mut BodyChanges,
+        budget: &mut Budget<'_>,
+    ) -> Result<usize, &'static str> {
         let desktop = rule.rule.scope == PrivacyScope::DesktopGitContext;
+        let targets = if desktop {
+            &mut self.desktop
+        } else {
+            &mut self.environment
+        };
+        if targets.is_none() {
+            *targets = Some(locate_contexts(body, desktop, budget)?);
+        }
+        let mut count = 0;
+        for target in targets.iter().flatten() {
+            budget.step()?;
+            // 先检查长度再复制，普通对话和工具输出不会进入事务副本
+            let text = body
+                .pointer(&target.path)
+                .and_then(Value::as_str)
+                .ok_or("上下文文本不存在")?;
+            let trimmed = text.trim();
+            let complete = trimmed.starts_with(target.open) && trimmed.ends_with(target.close);
+            if !complete {
+                if target.identified {
+                    return Err("已识别上下文不完整，可能已被截断");
+                }
+                continue;
+            }
+            budget.text(text)?;
+            count += changes.stage(body, &target.path, budget, |next, budget| {
+                let Value::String(text) = next else {
+                    return Err("上下文必须是文本");
+                };
+                if desktop {
+                    git(rule, text, budget)
+                } else {
+                    environment(rule, text, budget)
+                }
+            })?;
+        }
+        Ok(count)
+    }
+}
+
+fn locate_contexts(
+    body: &Value,
+    desktop: bool,
+    budget: &mut Budget<'_>,
+) -> Result<Vec<ContextTarget>, &'static str> {
+    let mut targets = Vec::new();
+    let Some(items) = body.get("input").and_then(Value::as_array) else {
+        return Ok(targets);
+    };
+    for (item_index, item) in items.iter().enumerate() {
+        budget.step()?;
+        let role = item.get("role").and_then(Value::as_str).unwrap_or("");
         if !(role == "user" || (!desktop && role == "developer")) {
             continue;
         }
-        let (kind, tag) = if desktop {
+        let (kind, open, close) = if desktop {
             (
                 "additional_content.codex_git_state",
-                "external_codex_git_state",
+                "<external_codex_git_state>",
+                "</external_codex_git_state>",
             )
         } else if role == "developer" {
             (
                 "additional_content.codex_apps_client_time_context",
-                "codex_apps_client_time_context",
+                "<codex_apps_client_time_context>",
+                "</codex_apps_client_time_context>",
             )
         } else {
-            ("environments.environment_context", "environment_context")
+            (
+                "environments.environment_context",
+                "<environment_context>",
+                "</environment_context>",
+            )
         };
-        let kinds = item
-            .pointer("/internal_chat_message_metadata_passthrough/content_item_kinds")
-            .cloned();
-        let Some(parts) = item.get_mut("content").and_then(Value::as_array_mut) else {
+        let kinds = item.pointer("/internal_chat_message_metadata_passthrough/content_item_kinds");
+        let Some(parts) = item.get("content").and_then(Value::as_array) else {
             continue;
         };
-        for (index, part) in parts.iter_mut().enumerate() {
-            if let Some(kinds) = &kinds
-                && kinds.get(index).and_then(Value::as_str) != Some(kind)
-            {
+        for (index, part) in parts.iter().enumerate() {
+            budget.step()?;
+            if kinds.is_some_and(|kinds| kinds.get(index).and_then(Value::as_str) != Some(kind)) {
                 continue;
             }
             if part.get("type").and_then(Value::as_str) != Some("input_text") {
                 continue;
             }
-            let Some(Value::String(text)) = part.get_mut("text") else {
+            let Some(text) = part.get("text").and_then(Value::as_str) else {
                 continue;
             };
-            let full = text.trim().starts_with(&format!("<{tag}>"))
-                && text.trim().ends_with(&format!("</{tag}>"));
-            if !full && kinds.is_none() {
+            let trimmed = text.trim();
+            if kinds.is_none() && !(trimmed.starts_with(open) && trimmed.ends_with(close)) {
                 continue;
             }
-            if !full {
-                return Err("已识别上下文不完整，可能已被截断");
-            }
-            budget.text(text)?;
-            count += if desktop {
-                git(rule, text, budget)?
-            } else {
-                environment(rule, text, budget)?
-            };
+            targets.push(ContextTarget {
+                path: format!("/input/{item_index}/content/{index}/text"),
+                open,
+                close,
+                identified: kinds.is_some(),
+            });
         }
     }
-    Ok(count)
+    Ok(targets)
 }
 
 fn git(
diff --git a/backend/crates/providers/openai/src/transport/privacy/changes.rs b/backend/crates/providers/openai/src/transport/privacy/changes.rs
new file mode 100644
index 000000000..e68a76337
--- /dev/null
+++ b/backend/crates/providers/openai/src/transport/privacy/changes.rs
@@ -0,0 +1,69 @@
+//! 暂存单条规则改动的正文片段，校验最终大小后统一提交
+
+use serde_json::Value;
+
+use super::{Budget, MAX_REQUEST_BYTES, encoded_size};
+
+pub(super) struct BodyChanges {
+    original_size: usize,
+    replacements: Vec<(String, Value)>,
+    removed_bytes: usize,
+    added_bytes: usize,
+}
+
+impl BodyChanges {
+    pub(super) fn new(original_size: usize) -> Self {
+        Self {
+            original_size,
+            replacements: Vec::new(),
+            removed_bytes: 0,
+            added_bytes: 0,
+        }
+    }
+
+    pub(super) fn stage(
+        &mut self,
+        body: &Value,
+        path: &str,
+        budget: &mut Budget<'_>,
+        apply: impl FnOnce(&mut Value, &mut Budget<'_>) -> Result<usize, &'static str>,
+    ) -> Result<usize, &'static str> {
+        let original = body.pointer(path).ok_or("目标正文片段不存在")?;
+        let mut next = original.clone();
+        let count = apply(&mut next, budget)?;
+        if count > 0 {
+            self.removed_bytes += if path.is_empty() {
+                self.original_size
+            } else {
+                encoded_size(original, MAX_REQUEST_BYTES)?
+            };
+            // 片段互不重叠，其编码字节总量是最终正文大小的下界
+            // 提前停止必然超限的改写，避免暂存所有膨胀后的上下文
+            self.added_bytes = self
+                .added_bytes
+                .checked_add(encoded_size(&next, MAX_REQUEST_BYTES)?)
+                .filter(|size| *size <= MAX_REQUEST_BYTES)
+                .ok_or("请求或预览样本超出大小限制")?;
+            self.replacements.push((path.to_owned(), next));
+        }
+        Ok(count)
+    }
+
+    pub(super) fn size(&self) -> Result<usize, &'static str> {
+        self.original_size
+            .checked_sub(self.removed_bytes)
+            .and_then(|size| size.checked_add(self.added_bytes))
+            .filter(|size| *size <= MAX_REQUEST_BYTES)
+            .ok_or("请求或预览样本超出大小限制")
+    }
+
+    pub(super) fn commit(self, body: &mut Value) {
+        // 路径来自本条规则执行前的正文，片段互不包含且提交前正文尚未改写
+        // 仅替换值，不增删这些路径的祖先，因此先前替换不会使后续路径失效
+        for (path, next) in self.replacements {
+            if let Some(target) = body.pointer_mut(&path) {
+                *target = next;
+            }
+        }
+    }
+}
diff --git a/backend/crates/providers/openai/src/transport/privacy/mod.rs b/backend/crates/providers/openai/src/transport/privacy/mod.rs
index 231b1ee9d..3ba622986 100644
--- a/backend/crates/providers/openai/src/transport/privacy/mod.rs
+++ b/backend/crates/providers/openai/src/transport/privacy/mod.rs
@@ -1,18 +1,15 @@
 //! OpenAI 隐私规则的统一编译与执行，供设置预览和实际出站共享
 
 mod carrier;
+mod changes;
 mod rule;
 mod selector;
 
-use std::{
-    collections::BTreeSet,
-    sync::Arc,
-    time::{Duration, Instant},
-};
+use std::{collections::BTreeSet, sync::Arc};
 
 use gateway_core::settings::privacy::{
     CodexPrivacyPolicy, CompiledPrivacyPolicy, PrivacyError, PrivacyFailureMode,
-    PrivacyPreviewRequest, PrivacyPreviewResult, PrivacyRuleOutcome,
+    PrivacyPreviewRequest, PrivacyPreviewResult, PrivacyRuleOutcome, PrivacyScope,
 };
 use reqwest::header::{HeaderMap, HeaderName, HeaderValue};
 use serde_json::Value;
@@ -36,7 +33,6 @@ impl std::fmt::Debug for Policy {
 }
 
 struct Budget<'a> {
-    started: Instant,
     steps: usize,
     text_bytes: usize,
     cancelled: &'a dyn Fn() -> bool,
@@ -48,8 +44,8 @@ impl Budget<'_> {
         if (self.cancelled)() {
             return Err("请求已取消或超时");
         }
-        if self.steps > 10_000 || self.started.elapsed() > Duration::from_millis(100) {
-            return Err("规则执行预算超限");
+        if self.steps > 10_000 {
+            return Err("规则执行步数超限");
         }
         Ok(())
     }
@@ -105,11 +101,12 @@ impl CompiledPrivacyPolicy for Policy {
     ) -> Result<Vec<PrivacyRuleOutcome>, PrivacyError> {
         let mut outcomes = Vec::new();
         let mut budget = Budget {
-            started: Instant::now(),
             steps: 0,
             text_bytes: 0,
             cancelled,
         };
+        let mut body_size = None;
+        let mut contexts = carrier::ContextIndex::default();
         for (rule_index, rule) in self.rules.iter().enumerate() {
             let mut outcome = PrivacyRuleOutcome {
                 rule_id: rule.rule.id.clone(),
@@ -121,22 +118,30 @@ impl CompiledPrivacyPolicy for Policy {
                 // 一条规则的所有承载副本同成同败，失败不会留下部分改写
                 let result = (|| {
                     budget.step()?;
-                    check_size(body, MAX_REQUEST_BYTES)?;
-                    let mut next_body = body.clone();
+                    let original_size =
+                        *body_size.get_or_insert_with(|| encoded_size(body, MAX_REQUEST_BYTES));
+                    let original_size = original_size?;
                     let mut next_headers = headers.clone();
                     let mut next_metadata = turn_metadata.clone();
-                    let count = carrier::apply(
+                    let mut changes = changes::BodyChanges::new(original_size);
+                    let count = carrier::prepare(
                         rule,
-                        &mut next_body,
+                        body,
                         &mut next_headers,
                         &mut next_metadata,
+                        &mut changes,
+                        &mut contexts,
                         &mut budget,
                     )?;
-                    check_size(&next_body, MAX_REQUEST_BYTES)?;
+                    let next_size = changes.size()?;
                     budget.step()?;
-                    *body = next_body;
+                    changes.commit(body);
                     *headers = next_headers;
                     *turn_metadata = next_metadata;
+                    body_size = Some(Ok(next_size));
+                    if count > 0 && rule.rule.scope == PrivacyScope::RequestBody {
+                        contexts = carrier::ContextIndex::default();
+                    }
                     Ok(count)
                 })();
                 match result {
@@ -223,6 +228,10 @@ pub fn preview(request: PrivacyPreviewRequest) -> Result<PrivacyPreviewResult, P
 }
 
 fn check_size(value: &Value, limit: usize) -> Result<(), &'static str> {
+    encoded_size(value, limit).map(|_| ())
+}
+
+fn encoded_size(value: &Value, limit: usize) -> Result<usize, &'static str> {
     struct Counter(usize);
     impl std::io::Write for Counter {
         fn write(&mut self, bytes: &[u8]) -> std::io::Result<usize> {
@@ -236,7 +245,9 @@ fn check_size(value: &Value, limit: usize) -> Result<(), &'static str> {
             Ok(())
         }
     }
-    serde_json::to_writer(Counter(limit), value).map_err(|_| "请求或预览样本超出大小限制")
+    let mut counter = Counter(limit);
+    serde_json::to_writer(&mut counter, value).map_err(|_| "请求或预览样本超出大小限制")?;
+    Ok(limit - counter.0)
 }
 
 impl super::client::CodexBackendClient {
diff --git a/backend/crates/providers/openai/tests/transport/privacy/changes.rs b/backend/crates/providers/openai/tests/transport/privacy/changes.rs
new file mode 100644
index 000000000..bedc9705a
--- /dev/null
+++ b/backend/crates/providers/openai/tests/transport/privacy/changes.rs
@@ -0,0 +1,210 @@
+//! 局部隐私事务的跨副本回滚、上下文定位失效与编码大小边界
+
+use super::{policy, rule, sample};
+use gateway_core::settings::privacy::*;
+use provider_openai::transport::privacy::{compile, preview};
+use serde_json::{Value, json};
+
+fn git_item(value: Value) -> Value {
+    json!({"role":"user","content":[{"type":"input_text","text":format!(
+        "<external_codex_git_state><environment_context><git>{value}</git></environment_context></external_codex_git_state>"
+    )}]})
+}
+
+#[test]
+fn failed_metadata_rule_preserves_body_headers_and_independent_metadata() {
+    let mut request = sample(
+        vec![rule(
+            PrivacyScope::TurnMetadata,
+            "$.secret",
+            PrivacyAction::RemoveField,
+        )],
+        json!({"turnMetadata":{"secret":true},"client_metadata":{"turnMetadata":42}}),
+    );
+    request.policy.on_error = PrivacyFailureMode::SkipRule;
+    request.turn_metadata = Some(r#"{"secret":true}"#.into());
+    request.headers.insert(
+        "x-codex-turn-metadata".into(),
+        vec![r#"{"secret":true}"#.into()],
+    );
+    let output = preview(request.clone()).unwrap();
+    assert_eq!(output.body, request.body);
+    assert_eq!(output.headers, request.headers);
+    assert_eq!(output.turn_metadata, request.turn_metadata);
+    assert_eq!(output.outcomes[0].status, "skipped");
+}
+
+#[test]
+fn malformed_later_git_copy_rolls_back_every_context() {
+    let first = git_item(json!({"secret":true}));
+    let mut second = first.clone();
+    second["content"][0]["text"] = json!(
+        "<external_codex_git_state><environment_context><git>invalid</git></environment_context></external_codex_git_state>"
+    );
+    let body = json!({"input":[first,second]});
+    let mut request = sample(
+        vec![rule(
+            PrivacyScope::DesktopGitContext,
+            "$.secret",
+            PrivacyAction::RemoveField,
+        )],
+        body.clone(),
+    );
+    request.policy.on_error = PrivacyFailureMode::SkipRule;
+    let output = preview(request).unwrap();
+    assert_eq!(output.body, body);
+    assert_eq!(output.outcomes[0].status, "skipped");
+}
+
+#[test]
+fn body_deletion_invalidates_context_positions_between_rules() {
+    let first = rule(
+        PrivacyScope::DesktopGitContext,
+        "$.first",
+        PrivacyAction::RemoveField,
+    );
+    let mut delete = rule(
+        PrivacyScope::RequestBody,
+        "$.input[0]",
+        PrivacyAction::RemoveField,
+    );
+    delete.id = "delete".into();
+    let mut last = rule(
+        PrivacyScope::DesktopGitContext,
+        "$.last",
+        PrivacyAction::RemoveField,
+    );
+    last.id = "last".into();
+    let output = preview(sample(
+        vec![first, delete, last],
+        json!({"input":[
+            git_item(json!({"first":1})),git_item(json!({"first":1,"last":2,"keep":true}))
+        ]}),
+    ))
+    .unwrap();
+    assert_eq!(
+        output
+            .outcomes
+            .iter()
+            .map(|o| o.matches)
+            .collect::<Vec<_>>(),
+        vec![2, 1, 1]
+    );
+    assert_eq!(
+        output.body,
+        json!({"input":[git_item(json!({"keep":true}))]})
+    );
+}
+
+#[test]
+fn cached_candidates_recheck_context_wrapper_after_text_replacement() {
+    let mut first = rule(
+        PrivacyScope::EnvironmentText,
+        "$",
+        PrivacyAction::RegexReplace,
+    );
+    first.pattern = Some("<environment_context>".into());
+    first.replacement = "<environment_context note=\"test\">".into();
+    let mut last = rule(
+        PrivacyScope::EnvironmentText,
+        "$",
+        PrivacyAction::RegexReplace,
+    );
+    last.id = "last".into();
+    last.pattern = Some("private".into());
+    last.replacement = "public".into();
+    let output = preview(sample(
+        vec![first, last],
+        json!({"input":[{"role":"user","content":[
+            {"type":"input_text","text":"<environment_context>private</environment_context>"}
+        ]}]}),
+    ))
+    .unwrap();
+    assert_eq!(output.outcomes[0].status, "applied");
+    assert_eq!(output.outcomes[1].status, "unmatched");
+    assert!(
+        output.body["input"][0]["content"][0]["text"]
+            .as_str()
+            .unwrap()
+            .contains("private")
+    );
+}
+
+#[test]
+fn unicode_reencoding_growth_rejects_and_rolls_back_only_current_rule() {
+    let mut remove = rule(
+        PrivacyScope::TurnMetadata,
+        "$.secret",
+        PrivacyAction::RemoveField,
+    );
+    remove.id = "remove".into();
+    let mut last = rule(
+        PrivacyScope::RequestHeader,
+        "x-remove",
+        PrivacyAction::RemoveField,
+    );
+    last.id = "last".into();
+    let mut config = policy(vec![remove, last]);
+    config.on_error = PrivacyFailureMode::SkipRule;
+    let compiled = compile(&config).unwrap();
+    let mut body = json!({"turnMetadata":json!({"secret":true,"keep":"界".repeat(100)}).to_string(),"padding":""});
+    let padding = 32 * 1024 * 1024 - serde_json::to_vec(&body).unwrap().len();
+    body["padding"] = json!("a".repeat(padding));
+    let original = body.clone();
+    let mut headers = reqwest::header::HeaderMap::new();
+    headers.insert("x-remove", "test".parse().unwrap());
+    let outcomes = compiled
+        .apply(&mut body, &mut headers, &mut None, &|| false)
+        .unwrap();
+    assert_eq!(body, original);
+    assert_eq!(
+        outcomes[0].reason.as_deref(),
+        Some("请求或预览样本超出大小限制")
+    );
+    assert_eq!(outcomes[1].status, "applied");
+    assert!(headers.is_empty());
+}
+
+#[test]
+fn cancellation_after_staging_leaves_every_carrier_unchanged() {
+    let config = policy(vec![rule(
+        PrivacyScope::TurnMetadata,
+        "$.secret",
+        PrivacyAction::RemoveField,
+    )]);
+    let compiled = compile(&config).unwrap();
+    let original =
+        json!({"turnMetadata":{"secret":true},"client_metadata":{"turnMetadata":{"secret":true}}});
+    // 覆盖每一个取消检查点，包括片段已暂存、尚未提交的最后一步
+    let mut successful = false;
+    for cancel_at in 1..64 {
+        let mut body = original.clone();
+        let mut headers = reqwest::header::HeaderMap::new();
+        headers.insert(
+            "x-codex-turn-metadata",
+            r#"{"secret":true}"#.parse().unwrap(),
+        );
+        let original_headers = headers.clone();
+        let mut metadata = Some(r#"{"secret":true}"#.to_owned());
+        let original_metadata = metadata.clone();
+        let calls = std::cell::Cell::new(0);
+        let result = compiled.apply(&mut body, &mut headers, &mut metadata, &|| {
+            calls.set(calls.get() + 1);
+            calls.get() >= cancel_at
+        });
+        match result {
+            Err(error) => {
+                assert_eq!(error.reason, "请求已取消或超时");
+                assert_eq!(body, original);
+                assert_eq!(headers, original_headers);
+                assert_eq!(metadata, original_metadata);
+            }
+            Ok(outcomes) => {
+                assert_eq!(outcomes[0].matches, 4);
+                successful = true;
+                break;
+            }
+        }
+    }
+    assert!(successful);
+}
diff --git a/backend/crates/providers/openai/tests/transport/privacy/mod.rs b/backend/crates/providers/openai/tests/transport/privacy/mod.rs
index 4c41fc8f1..cecf1c006 100644
--- a/backend/crates/providers/openai/tests/transport/privacy/mod.rs
+++ b/backend/crates/providers/openai/tests/transport/privacy/mod.rs
@@ -1,5 +1,7 @@
 //! 隐私规则的多承载一致性、自由字段配置、条件删除与有界失败合同
 
+mod changes;
+
 use gateway_core::settings::privacy::*;
 use provider_openai::transport::privacy::{compile, preview};
 use serde_json::{Value, json};
@@ -291,7 +293,7 @@ fn privacy_validates_regex_paths_captures_and_execution_limits() {
     let error = policy
         .apply(&mut body, &mut Default::default(), &mut None, &|| false)
         .unwrap_err();
-    assert_eq!(error.reason, "规则执行预算超限");
+    assert_eq!(error.reason, "规则执行步数超限");
     assert_eq!(body, original);
     assert!(
         policy
diff --git a/docs/api.md b/docs/api.md
index 7fa3af480..eadce70da 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -1433,7 +1433,8 @@ JSON 路径支持 `$`、`.成员`、`["带特殊字符的键"]`、`[索引]`、`
 `replaceAll` 控制首个或全部匹配，另支持忽略大小写和多行锚点。最多 32 条规则，路径最多 16 层、1024 字节，
 模式与替换内容分别最多 4096 字节，固定值编码后最多 4096 字节。XML 上下文最多 10000 个节点，环境文本最多 64 层。
 执行限制为正文 32 MiB、单目标文本及编码后的上下文 1 MiB、
-累计处理文本 16 MiB、10000 次访问与匹配步骤、100 ms 检查预算；时间预算在处理检查点检查，不是硬实时中断
+累计处理文本 16 MiB、每次执行 10000 次访问与匹配步骤。
+执行检查点响应请求取消，步数超限报告「规则执行步数超限」，不以固定墙钟时长判定规则失败
 
 执行失败时，`skip_rule` 撤销本条规则在所有副本上的修改并继续，意味着本条脱敏未完成；
 `reject_request` 阻止发送并返回本地请求错误，不因该错误自动重试或换号。设置保存时校验所有规则，包含未启用的规则