Render code comment directives in TUI replay (#26554)

## Summary

Resumed Codex App or VS Code review sessions can contain
`::code-comment` directives that the TUI previously displayed verbatim
because only rich clients interpret them.

This change rewrites valid line-start directives into readable Markdown
during assistant-message parsing, using the session working directory
for relative file paths. The fallback is applied consistently to live
messages, replayed transcripts, and resume previews while preserving
malformed directives and existing `::git-*` parsing.

## Before

The TUI exposed the raw client directive:

```text
::code-comment{title="Fix body= parsing" body="Keep role=\"tab\", ::git-stage{cwd=/tmp}, file=, and \n literal." file="/repo/src/app.ts" start=10 end=12 priority="P2"}
```

## After

The same directive is rendered as readable review feedback:

```text
- [P2] Fix body= parsing — src/app.ts:10-12
  Keep role="tab", ::git-stage{cwd=/tmp}, file=, and \n literal.
```

Fixes #25658

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

@@ -38,7 +38,8 @@ impl ChatWidget {
             // Consolidate the run of streaming AgentMessageCells into a single AgentMarkdownCell
             // that can re-render from source on resize.
             if let Some(source) = source {
-                let source = parse_assistant_markdown(&source).visible_markdown;
+                let source =
+                    parse_assistant_markdown(&source, self.config.cwd.as_path()).visible_markdown;
                 self.app_event_tx.send(AppEvent::ConsolidateAgentMessage {
                     source,
                     cwd: self.config.cwd.to_path_buf(),
@@ -261,7 +262,7 @@ impl ChatWidget {
                 AgentMessageContent::Text { text } => message.push_str(text),
             }
         }
-        let parsed = parse_assistant_markdown(&message);
+        let parsed = parse_assistant_markdown(&message, self.config.cwd.as_path());
         self.finalize_completed_assistant_message(
             (!parsed.visible_markdown.is_empty()).then_some(parsed.visible_markdown.as_str()),
         );

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

@@ -89,9 +89,9 @@ impl ChatWidget {
         // source only when no earlier item-level event (AgentMessageItem, plan
         // commit, review output) already recorded markdown for this turn. This
         // prevents the final summary from overwriting a more specific source.
-        let sanitized_last_agent_message = last_agent_message
-            .as_deref()
-            .map(|message| parse_assistant_markdown(message).visible_markdown);
+        let sanitized_last_agent_message = last_agent_message.as_deref().map(|message| {
+            parse_assistant_markdown(message, self.config.cwd.as_path()).visible_markdown
+        });
         if let Some(message) = sanitized_last_agent_message
             .as_ref()
             .filter(|message| !message.is_empty())

codex-rs/tui/src/git_action_directives.rs

@@ -1,6 +1,8 @@
-//! Codex App git action directives embedded in assistant markdown.
+//! Codex App directives embedded in assistant markdown.
 
+use std::collections::HashMap;
 use std::collections::HashSet;
+use std::path::Path;
 
 #[derive(Clone, Debug, Eq, Hash, PartialEq)]
 pub(crate) enum GitActionDirective {
@@ -50,12 +52,16 @@ impl ParsedAssistantMarkdown {
     }
 }
 
-pub(crate) fn parse_assistant_markdown(markdown: &str) -> ParsedAssistantMarkdown {
+pub(crate) fn parse_assistant_markdown(markdown: &str, cwd: &Path) -> ParsedAssistantMarkdown {
     let mut git_actions = Vec::new();
     let mut seen = HashSet::new();
     let mut visible_lines = Vec::new();
 
     for line in markdown.lines() {
+        if let Some(rewritten) = rewrite_code_comment_line(line, cwd) {
+            visible_lines.push(rewritten.trim_end().to_string());
+            continue;
+        }
         let (visible_line, line_actions) = strip_line_directives(line);
         for action in line_actions {
             if seen.insert(action.clone()) {
@@ -78,6 +84,53 @@ pub(crate) fn parse_assistant_markdown(markdown: &str) -> ParsedAssistantMarkdow
     }
 }
 
+fn rewrite_code_comment_line(line: &str, cwd: &Path) -> Option<String> {
+    let content = line.trim_start_matches([' ', '\t']);
+    let indent = &line[..line.len() - content.len()];
+    let marker_length = content.bytes().take_while(|byte| *byte == b':').count();
+    if !(1..=3).contains(&marker_length) {
+        return None;
+    }
+
+    let directive = content[marker_length..].strip_prefix("code-comment{")?;
+    let (attributes, suffix) = directive.rsplit_once('}')?;
+    let attributes = parse_code_comment_attributes(attributes)?;
+    let title = attributes.get("title")?;
+    let body = attributes.get("body")?;
+    let file = attributes.get("file")?;
+    let title = title.trim();
+    let body = body.trim();
+    let file = file.trim();
+    (!title.is_empty() && !body.is_empty() && !file.is_empty()).then_some(())?;
+
+    let start = directive_integer(&attributes, "start").unwrap_or(1).max(1);
+    let end = directive_integer(&attributes, "end")
+        .unwrap_or(start)
+        .max(start);
+    let title = if title_has_priority(title) {
+        title.to_string()
+    } else if let Some(priority @ 0..=3) = directive_integer(&attributes, "priority") {
+        format!("[P{priority}] {title}")
+    } else {
+        title.to_string()
+    };
+    let file_path = Path::new(file);
+    let file = file_path
+        .strip_prefix(cwd)
+        .unwrap_or(file_path)
+        .to_string_lossy()
+        .replace('\\', "/");
+    let location = if start == end {
+        format!("{file}:{start}")
+    } else {
+        format!("{file}:{start}-{end}")
+    };
+
+    Some(format!(
+        "{indent}- {title} — {location}\n{indent}  {body}{suffix}"
+    ))
+}
+
 fn strip_line_directives(line: &str) -> (String, Vec<GitActionDirective>) {
     let mut visible = String::new();
     let mut actions = Vec::new();
@@ -106,6 +159,46 @@ fn strip_line_directives(line: &str) -> (String, Vec<GitActionDirective>) {
     (visible, actions)
 }
 
+fn directive_integer(attributes: &HashMap<String, String>, name: &str) -> Option<i64> {
+    attributes
+        .get(name)?
+        .trim()
+        .trim_start_matches(['P', 'p'])
+        .parse()
+        .ok()
+}
+
+fn title_has_priority(title: &str) -> bool {
+    let bytes = title.trim_start().as_bytes();
+    bytes.len() >= 4
+        && bytes[0] == b'['
+        && matches!(bytes[1], b'P' | b'p')
+        && bytes[2].is_ascii_digit()
+        && bytes[3] == b']'
+}
+
+fn parse_code_comment_attributes(input: &str) -> Option<HashMap<String, String>> {
+    let mut attributes = HashMap::new();
+    let mut rest = input.trim();
+    while !rest.is_empty() {
+        let equals = rest.find('=')?;
+        let name = rest[..equals].trim();
+        if name.is_empty() {
+            return None;
+        }
+        rest = rest[equals + 1..].trim_start();
+        let (value, next) = if let Some(quoted) = rest.strip_prefix('"') {
+            parse_quoted_value(quoted)?
+        } else {
+            let end = rest.find(char::is_whitespace).unwrap_or(rest.len());
+            (rest[..end].to_string(), &rest[end..])
+        };
+        attributes.insert(name.to_string(), value);
+        rest = next.trim_start();
+    }
+    Some(attributes)
+}
+
 fn parse_git_action(name: &str, attributes: &str) -> Option<GitActionDirective> {
     let attrs = parse_attributes(attributes)?;
     let cwd = attrs.get("cwd")?.clone();
@@ -153,14 +246,36 @@ fn parse_attributes(input: &str) -> Option<std::collections::HashMap<String, Str
     Some(attrs)
 }
 
+fn parse_quoted_value(input: &str) -> Option<(String, &str)> {
+    let mut value = String::new();
+    let mut characters = input.char_indices().peekable();
+
+    while let Some((index, character)) = characters.next() {
+        if character == '"' {
+            return Some((value, &input[index + 1..]));
+        }
+        match character {
+            '\\' if characters.peek().is_some_and(|(_, next)| *next == '"') => {
+                value.push('"');
+                characters.next();
+            }
+            _ => value.push(character),
+        }
+    }
+
+    None
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
+    use pretty_assertions::assert_eq;
 
     #[test]
     fn strips_and_parses_git_action_directives() {
         let parsed = parse_assistant_markdown(
-            "Done\n\n::git-stage{cwd=\"/repo\"} ::git-push{cwd=\"/repo\" branch=\"feat/x\"}",
+            "Done\n\n::git-stage{cwd=\"/repo\"} ::git-push{cwd=\"/repo\" branch=\"feat/x\"} ::git-stage{cwd=\"C:\\repo\\\"}",
+            Path::new("/repo"),
         );
 
         assert_eq!(parsed.visible_markdown, "Done");
@@ -174,22 +289,50 @@ mod tests {
                     cwd: "/repo".to_string(),
                     branch: "feat/x".to_string(),
                 },
+                GitActionDirective::Stage {
+                    cwd: "C:\\repo\\".to_string(),
+                },
             ]
         );
     }
 
     #[test]
     fn hides_malformed_directives_without_materializing_rows() {
-        let parsed = parse_assistant_markdown("Done ::git-push{cwd=\"/repo\"}");
+        let parsed = parse_assistant_markdown("Done ::git-push{cwd=\"/repo\"}", Path::new("/repo"));
 
         assert_eq!(parsed.visible_markdown, "Done");
         assert!(parsed.git_actions.is_empty());
     }
 
+    #[test]
+    fn renders_code_comment_directives_as_markdown() {
+        let parsed = parse_assistant_markdown(
+            concat!(
+                "Found two issues.\n\n",
+                r#"::code-comment{title="Fix body= parsing" body="Keep role=\"tab\", ::git-stage{cwd=/tmp}, file=, and \n literal." file="/repo/src/app.ts" start=10 end=12 priority="P2"}"#,
+                "\n\n",
+                r#":::code-comment{title="[P1] Clamp the range" body="The line range should match the App." file="codex/src/range.ts" start=8 end=2 priority=3}"#,
+            ),
+            Path::new("/repo"),
+        );
+
+        insta::assert_snapshot!("code_comment_directive_fallback", parsed.visible_markdown);
+        assert!(parsed.git_actions.is_empty());
+    }
+
+    #[test]
+    fn preserves_non_directive_and_malformed_code_comment_text() {
+        let markdown = "Mention `::code-comment{title=\"Example\"}` inline.\n::code-comment{title=\"Missing body\" file=\"/repo/src/app.ts\"}";
+        let parsed = parse_assistant_markdown(markdown, Path::new("/repo"));
+
+        assert_eq!(parsed.visible_markdown, markdown);
+    }
+
     #[test]
     fn last_created_branch_cwd_uses_the_last_matching_directive() {
         let parsed = parse_assistant_markdown(
             "::git-create-branch{cwd=\"/first\" branch=\"first\"}\n::git-push{cwd=\"/repo\" branch=\"first\"}\n::git-create-branch{cwd=\"/second\" branch=\"second\"}",
+            Path::new("/repo"),
         );
 
         assert_eq!(parsed.last_created_branch_cwd(), Some("/second"));

codex-rs/tui/src/resume_picker.rs

@@ -774,6 +774,7 @@ async fn load_transcript_preview(
         .thread_read(thread_id, /*include_turns*/ true)
         .await
         .map_err(std::io::Error::other)?;
+    let cwd = thread.cwd.as_path();
     let mut lines = thread
         .turns
         .iter()
@@ -794,7 +795,7 @@ async fn load_transcript_preview(
             }),
             ThreadItem::AgentMessage { text, .. } => Some(TranscriptPreviewLine {
                 speaker: TranscriptPreviewSpeaker::Assistant,
-                text: parse_assistant_markdown(text).visible_markdown,
+                text: parse_assistant_markdown(text, cwd).visible_markdown,
             }),
             _ => None,
         })

codex-rs/tui/src/resume_picker/transcript.rs

@@ -67,7 +67,7 @@ pub(crate) fn thread_to_transcript_cells(
                 }));
             }
             ThreadItem::AgentMessage { text, .. } => {
-                let parsed = parse_assistant_markdown(text);
+                let parsed = parse_assistant_markdown(text, cwd);
                 if !parsed.visible_markdown.trim().is_empty() {
                     cells.push(Arc::new(AgentMarkdownCell::new(
                         parsed.visible_markdown,

codex-rs/tui/src/snapshots/codex_tui__git_action_directives__tests__code_comment_directive_fallback.snap

@@ -0,0 +1,11 @@
+---
+source: tui/src/git_action_directives.rs
+expression: parsed.visible_markdown
+---
+Found two issues.
+
+- [P2] Fix body= parsing — src/app.ts:10-12
+  Keep role="tab", ::git-stage{cwd=/tmp}, file=, and \n literal.
+
+- [P1] Clamp the range — codex/src/range.ts:8
+  The line range should match the App.