cleanup

## Summary
We ideally shouldn't make it to this point in the first place, but if we
do try to append a rule that already exists, we shouldn't append the
same rule twice.

## Testing
- [x] Added unit test for this case

codex-rs/core/src/client.rs

@@ -1,3 +1,4 @@
+use std::path::PathBuf;
 use std::sync::Arc;
 use std::sync::OnceLock;
 
@@ -5,6 +6,7 @@ use crate::api_bridge::CoreAuthProvider;
 use crate::api_bridge::auth_provider_from_auth;
 use crate::api_bridge::map_api_error;
 use crate::auth::UnauthorizedRecovery;
+use crate::turn_metadata::build_turn_metadata_header;
 use codex_api::AggregateStreamExt;
 use codex_api::ChatClient as ApiChatClient;
 use codex_api::CompactClient as ApiCompactClient;
@@ -72,6 +74,7 @@ use crate::transport_manager::TransportManager;
 
 pub const WEB_SEARCH_ELIGIBLE_HEADER: &str = "x-oai-web-search-eligible";
 pub const X_CODEX_TURN_STATE_HEADER: &str = "x-codex-turn-state";
+pub const X_CODEX_TURN_METADATA_HEADER: &str = "x-codex-turn-metadata";
 
 #[derive(Debug)]
 struct ModelClientState {
@@ -108,6 +111,10 @@ pub struct ModelClientSession {
     /// keep sending it unchanged between turn requests (e.g., for retries, incremental
     /// appends, or continuation requests), and must not send it between different turns.
     turn_state: Arc<OnceLock<String>>,
+    /// Turn-scoped metadata attached to every request in the turn.
+    turn_metadata_header: Option<HeaderValue>,
+    /// Working directory used to lazily compute turn metadata at send time.
+    turn_metadata_cwd: Option<PathBuf>,
 }
 
 #[allow(clippy::too_many_arguments)]
@@ -140,13 +147,21 @@ impl ModelClient {
         }
     }
 
-    pub fn new_session(&self) -> ModelClientSession {
+    pub fn new_session(
+        &self,
+        turn_metadata_header: Option<String>,
+        turn_metadata_cwd: Option<PathBuf>,
+    ) -> ModelClientSession {
+        let turn_metadata_header =
+            turn_metadata_header.and_then(|value| HeaderValue::from_str(&value).ok());
         ModelClientSession {
             state: Arc::clone(&self.state),
             connection: None,
             websocket_last_items: Vec::new(),
             transport_manager: self.state.transport_manager.clone(),
             turn_state: Arc::new(OnceLock::new()),
+            turn_metadata_header,
+            turn_metadata_cwd,
         }
     }
 }
@@ -257,6 +272,21 @@ impl ModelClient {
 }
 
 impl ModelClientSession {
+    async fn ensure_turn_metadata_header(&mut self) {
+        if self.turn_metadata_header.is_some() {
+            return;
+        }
+        let Some(cwd) = self.turn_metadata_cwd.as_deref() else {
+            return;
+        };
+        let Some(value) = build_turn_metadata_header(cwd).await else {
+            return;
+        };
+        if let Ok(header_value) = HeaderValue::from_str(value.as_str()) {
+            self.turn_metadata_header = Some(header_value);
+        }
+    }
+
     /// Streams a single model turn using either the Responses or Chat
     /// Completions wire API, depending on the configured provider.
     ///
@@ -264,6 +294,9 @@ impl ModelClientSession {
     /// based on the `show_raw_agent_reasoning` flag in the config.
     pub async fn stream(&mut self, prompt: &Prompt) -> Result<ResponseStream> {
         let wire_api = self.state.provider.wire_api;
+        if matches!(wire_api, WireApi::Responses) {
+            self.ensure_turn_metadata_header().await;
+        }
         match wire_api {
             WireApi::Responses => {
                 let websocket_enabled = self.responses_websocket_enabled()
@@ -380,7 +413,11 @@ impl ModelClientSession {
             store_override: None,
             conversation_id: Some(conversation_id),
             session_source: Some(self.state.session_source.clone()),
-            extra_headers: build_responses_headers(&self.state.config, Some(&self.turn_state)),
+            extra_headers: build_responses_headers(
+                &self.state.config,
+                Some(&self.turn_state),
+                self.turn_metadata_header.as_ref(),
+            ),
             compression,
             turn_state: Some(Arc::clone(&self.turn_state)),
         }
@@ -713,6 +750,7 @@ fn experimental_feature_headers(config: &Config) -> ApiHeaderMap {
 fn build_responses_headers(
     config: &Config,
     turn_state: Option<&Arc<OnceLock<String>>>,
+    turn_metadata_header: Option<&HeaderValue>,
 ) -> ApiHeaderMap {
     let mut headers = experimental_feature_headers(config);
     headers.insert(
@@ -731,6 +769,9 @@ fn build_responses_headers(
     {
         headers.insert(X_CODEX_TURN_STATE_HEADER, header_value);
     }
+    if let Some(header_value) = turn_metadata_header {
+        headers.insert(X_CODEX_TURN_METADATA_HEADER, header_value.clone());
+    }
     headers
 }
 

codex-rs/core/src/codex.rs

@@ -119,6 +119,7 @@ use crate::error::Result as CodexResult;
 use crate::exec::StreamOutput;
 use crate::exec_policy::ExecPolicyUpdateError;
 use crate::feedback_tags;
+use crate::git_info::get_git_repo_root;
 use crate::instructions::UserInstructions;
 use crate::mcp::CODEX_APPS_MCP_SERVER_NAME;
 use crate::mcp::auth::compute_auth_statuses;
@@ -503,8 +504,9 @@ pub(crate) struct TurnContext {
     pub(crate) tool_call_gate: Arc<ReadinessFlag>,
     pub(crate) truncation_policy: TruncationPolicy,
     pub(crate) dynamic_tools: Vec<DynamicToolSpec>,
+    /// Per-turn metadata serialized as a header value for outbound model requests.
+    pub(crate) turn_metadata_header: Option<String>,
 }
-
 impl TurnContext {
     pub(crate) fn resolve_path(&self, path: Option<String>) -> PathBuf {
         path.as_ref()
@@ -705,6 +707,7 @@ impl Session {
             tool_call_gate: Arc::new(ReadinessFlag::new()),
             truncation_policy: model_info.truncation_policy.into(),
             dynamic_tools: session_configuration.dynamic_tools.clone(),
+            turn_metadata_header: None,
         }
     }
 
@@ -3176,6 +3179,7 @@ async fn spawn_review_thread(
         tool_call_gate: Arc::new(ReadinessFlag::new()),
         dynamic_tools: parent_turn_context.dynamic_tools.clone(),
         truncation_policy: model_info.truncation_policy.into(),
+        turn_metadata_header: None,
     };
 
     // Seed the child task with the review prompt as the initial user message.
@@ -3379,7 +3383,10 @@ pub(crate) async fn run_turn(
     // many turns, from the perspective of the user, it is a single turn.
     let turn_diff_tracker = Arc::new(tokio::sync::Mutex::new(TurnDiffTracker::new()));
 
-    let mut client_session = turn_context.client.new_session();
+    let mut client_session = turn_context.client.new_session(
+        turn_context.turn_metadata_header.clone(),
+        Some(turn_context.cwd.clone()),
+    );
 
     loop {
         // Note that pending_input would be something like a message the user
@@ -4442,8 +4449,6 @@ pub(super) fn get_last_assistant_message_from_turn(responses: &[ResponseItem]) -
 
 #[cfg(test)]
 pub(crate) use tests::make_session_and_context;
-
-use crate::git_info::get_git_repo_root;
 #[cfg(test)]
 pub(crate) use tests::make_session_and_context_with_rx;
 

codex-rs/core/src/compact.rs

@@ -335,7 +335,10 @@ async fn drain_to_completed(
     turn_context: &TurnContext,
     prompt: &Prompt,
 ) -> CodexResult<()> {
-    let mut client_session = turn_context.client.new_session();
+    let mut client_session = turn_context.client.new_session(
+        turn_context.turn_metadata_header.clone(),
+        Some(turn_context.cwd.clone()),
+    );
     let mut stream = client_session.stream(prompt).await?;
     loop {
         let maybe_event = stream.next().await;

codex-rs/core/src/environment_context.rs

@@ -28,6 +28,7 @@ impl EnvironmentContext {
             cwd,
             // should compare all fields except shell
             shell: _,
+            ..
         } = other;
 
         self.cwd == *cwd
@@ -66,6 +67,7 @@ impl EnvironmentContext {
 
         let shell_name = self.shell.name();
         lines.push(format!("  <shell>{shell_name}</shell>"));
+
         lines.push(ENVIRONMENT_CONTEXT_CLOSE_TAG.to_string());
         lines.join("\n")
     }

codex-rs/core/src/git_info.rs

@@ -1,3 +1,4 @@
+use std::collections::BTreeMap;
 use std::collections::HashSet;
 use std::path::Path;
 use std::path::PathBuf;
@@ -109,6 +110,92 @@ pub async fn collect_git_info(cwd: &Path) -> Option<GitInfo> {
     Some(git_info)
 }
 
+/// Collect fetch remotes in a multi-root-friendly format: {"origin": "https://..."}.
+pub async fn get_git_remote_urls(cwd: &Path) -> Option<BTreeMap<String, String>> {
+    let is_git_repo = run_git_command_with_timeout(&["rev-parse", "--git-dir"], cwd)
+        .await?
+        .status
+        .success();
+    if !is_git_repo {
+        return None;
+    }
+
+    get_git_remote_urls_assume_git_repo(cwd).await
+}
+
+/// Collect fetch remotes without checking whether `cwd` is in a git repo.
+pub async fn get_git_remote_urls_assume_git_repo(cwd: &Path) -> Option<BTreeMap<String, String>> {
+    get_git_remote_urls_assume_git_repo_with_timeout(cwd, GIT_COMMAND_TIMEOUT).await
+}
+
+/// Collect fetch remotes without checking whether `cwd` is in a git repo,
+/// using the provided timeout.
+pub async fn get_git_remote_urls_assume_git_repo_with_timeout(
+    cwd: &Path,
+    timeout_dur: TokioDuration,
+) -> Option<BTreeMap<String, String>> {
+    let output = run_git_command_with_timeout_override(&["remote", "-v"], cwd, timeout_dur).await?;
+    if !output.status.success() {
+        return None;
+    }
+
+    let stdout = String::from_utf8(output.stdout).ok()?;
+    parse_git_remote_urls(stdout.as_str())
+}
+
+/// Return the current HEAD commit hash without checking whether `cwd` is in a git repo.
+pub async fn get_head_commit_hash(cwd: &Path) -> Option<String> {
+    get_head_commit_hash_with_timeout(cwd, GIT_COMMAND_TIMEOUT).await
+}
+
+/// Return the current HEAD commit hash without checking whether `cwd` is in a
+/// git repo, using the provided timeout.
+pub async fn get_head_commit_hash_with_timeout(
+    cwd: &Path,
+    timeout_dur: TokioDuration,
+) -> Option<String> {
+    let output =
+        run_git_command_with_timeout_override(&["rev-parse", "HEAD"], cwd, timeout_dur).await?;
+    if !output.status.success() {
+        return None;
+    }
+
+    let stdout = String::from_utf8(output.stdout).ok()?;
+    let hash = stdout.trim();
+    if hash.is_empty() {
+        None
+    } else {
+        Some(hash.to_string())
+    }
+}
+
+fn parse_git_remote_urls(stdout: &str) -> Option<BTreeMap<String, String>> {
+    let mut remotes = BTreeMap::new();
+    for line in stdout.lines() {
+        let Some(fetch_line) = line.strip_suffix(" (fetch)") else {
+            continue;
+        };
+
+        let Some((name, url_part)) = fetch_line
+            .split_once('\t')
+            .or_else(|| fetch_line.split_once(' '))
+        else {
+            continue;
+        };
+
+        let url = url_part.trim_start();
+        if !url.is_empty() {
+            remotes.insert(name.to_string(), url.to_string());
+        }
+    }
+
+    if remotes.is_empty() {
+        None
+    } else {
+        Some(remotes)
+    }
+}
+
 /// A minimal commit summary entry used for pickers (subject + timestamp + sha).
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct CommitLogEntry {
@@ -185,11 +272,19 @@ pub async fn git_diff_to_remote(cwd: &Path) -> Option<GitDiffToRemote> {
 
 /// Run a git command with a timeout to prevent blocking on large repositories
 async fn run_git_command_with_timeout(args: &[&str], cwd: &Path) -> Option<std::process::Output> {
-    let result = timeout(
-        GIT_COMMAND_TIMEOUT,
-        Command::new("git").args(args).current_dir(cwd).output(),
-    )
-    .await;
+    run_git_command_with_timeout_override(args, cwd, GIT_COMMAND_TIMEOUT).await
+}
+
+/// Run a git command with a caller-provided timeout.
+async fn run_git_command_with_timeout_override(
+    args: &[&str],
+    cwd: &Path,
+    timeout_dur: TokioDuration,
+) -> Option<std::process::Output> {
+    let mut command = Command::new("git");
+    command.args(args).current_dir(cwd);
+    command.kill_on_drop(true);
+    let result = timeout(timeout_dur, command.output()).await;
 
     match result {
         Ok(Ok(output)) => Some(output),

codex-rs/core/src/lib.rs

@@ -101,6 +101,7 @@ pub mod state_db;
 pub mod terminal;
 mod tools;
 pub mod turn_diff_tracker;
+mod turn_metadata;
 pub use rollout::ARCHIVED_SESSIONS_SUBDIR;
 pub use rollout::INTERACTIVE_SESSION_SOURCES;
 pub use rollout::RolloutRecorder;
@@ -130,6 +131,7 @@ pub mod util;
 
 pub use apply_patch::CODEX_APPLY_PATCH_ARG1;
 pub use client::WEB_SEARCH_ELIGIBLE_HEADER;
+pub use client::X_CODEX_TURN_METADATA_HEADER;
 pub use command_safety::is_dangerous_command;
 pub use command_safety::is_safe_command;
 pub use exec_policy::ExecPolicyError;

codex-rs/core/src/turn_metadata.rs

@@ -0,0 +1,47 @@
+use std::collections::BTreeMap;
+use std::path::Path;
+
+use serde::Serialize;
+use tokio::time::Duration as TokioDuration;
+
+use crate::git_info::get_git_remote_urls_assume_git_repo_with_timeout;
+use crate::git_info::get_git_repo_root;
+use crate::git_info::get_head_commit_hash_with_timeout;
+
+const TURN_METADATA_TIMEOUT: TokioDuration = TokioDuration::from_millis(150);
+
+#[derive(Serialize)]
+struct TurnMetadataWorkspace {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    associated_remote_urls: Option<BTreeMap<String, String>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    latest_git_commit_hash: Option<String>,
+}
+
+#[derive(Serialize)]
+struct TurnMetadata {
+    workspaces: BTreeMap<String, TurnMetadataWorkspace>,
+}
+
+/// this happens at request send time only
+pub(crate) async fn build_turn_metadata_header(cwd: &Path) -> Option<String> {
+    let repo_root = get_git_repo_root(cwd)?;
+
+    let (latest_git_commit_hash, associated_remote_urls) = tokio::join!(
+        get_head_commit_hash_with_timeout(cwd, TURN_METADATA_TIMEOUT),
+        get_git_remote_urls_assume_git_repo_with_timeout(cwd, TURN_METADATA_TIMEOUT)
+    );
+    if latest_git_commit_hash.is_none() && associated_remote_urls.is_none() {
+        return None;
+    }
+
+    let mut workspaces = BTreeMap::new();
+    workspaces.insert(
+        repo_root.to_string_lossy().into_owned(),
+        TurnMetadataWorkspace {
+            associated_remote_urls,
+            latest_git_commit_hash,
+        },
+    );
+    serde_json::to_string(&TurnMetadata { workspaces }).ok()
+}

codex-rs/core/templates/model_instructions/gpt-5.2-codex_instructions_template.md

@@ -2,79 +2,56 @@ You are Codex, a coding agent based on GPT-5. You and the user share the same wo
 
 {{ personality }}
 
-# Working with the user
-
-You interact with the user through a terminal. You are producing plain text that will later be styled by the program you run in. Formatting should make results easy to scan, but not feel mechanical. Use judgment to decide how much structure adds value. Follow the formatting rules exactly. 
-
-## Final answer formatting rules
-- You may format with GitHub-flavored Markdown.
-- Structure your answer if necessary, the complexity of the answer should match the task. If the task is simple, your answer should be a one-liner. Order sections from general to specific to supporting.
+## Tone and style
+- Anything you say outside of tool use is shown to the user. Do not narrate abstractly; explain what you are doing and why, using plain language.
+- Output will be rendered in a command line interface or minimal UI so keep responses tight, scannable, and low-noise. Generally avoid the use of emojis. You may format with GitHub-flavored Markdown.
 - Never use nested bullets. Keep lists flat (single level). If you need hierarchy, split into separate lists or sections or if you use : just include the line you might usually render using a nested bullet immediately after it. For numbered lists, only use the `1. 2. 3.` style markers (with a period), never `1)`.
+- When writing a final assistant response, state the solution first before explaining your answer. The complexity of the answer should match the task. If the task is simple, your answer should be short. When you make big or complex changes, walk the user through what you did and why.
 - Headers are optional, only use them when you think they are necessary. If you do use them, use short Title Case (1-3 words) wrapped in **…**. Don't add a blank line.
-- Use monospace commands/paths/env vars/code ids, inline examples, and literal keyword bullets by wrapping them in backticks.
 - Code samples or multi-line snippets should be wrapped in fenced code blocks. Include an info string as often as possible.
-- File References: Never output the content of large files, just provide references. When referencing files in your response follow the below rules:
-  * Use inline code to make file paths clickable.
-  * Each reference should have a stand alone path. Even if it's the same file.
-  * Accepted: absolute, workspace‑relative, a/ or b/ diff prefixes, or bare filename/suffix.
-  * Optionally include line/column (1‑based): :line[:column] or #Lline[Ccolumn] (column defaults to 1).
-  * Do not use URIs like file://, vscode://, or https://.
-  * Do not provide range of lines
-  * Examples: src/app.ts, src/app.ts:42, b/server/index.js#L10, C:\repo\project\main.rs:12:5
-- Don’t use emojis.
-
-
-## Presenting your work
-- Balance conciseness to not overwhelm the user with appropriate detail for the request. Do not narrate abstractly; explain what you are doing and why.
+- Never output the content of large files, just provide references. Use inline code to make file paths clickable; each reference should have a stand alone path, even if it's the same file. Paths may be absolute, workspace-relative, a//b/ diff-prefixed, or bare filename/suffix; locations may be :line[:column] or #Lline[Ccolumn] (1-based; column defaults to 1). Do not use file://, vscode://, or https://, and do not provide line ranges. Examples: src/app.ts, src/app.ts:42, b/server/index.js#L10, C:\repo\project\main.rs:12:5
 - The user does not see command execution outputs. When asked to show the output of a command (e.g. `git show`), relay the important details in your answer or summarize the key lines so the user understands the result.
 - Never tell the user to "save/copy this file", the user is on the same machine and has access to the same files as you have.
-- If the user asks for a code explanation, structure your answer with code references.
-- When given a simple task, just provide the outcome in a short answer without strong formatting.
-- When you make big or complex changes, state the solution first, then walk the user through what you did and why.
-- For casual chit-chat, just chat.
-- Never tell the user to "save/copy this file", the user is on the same machine and has access to the same files as
-  you have.
 - If you weren't able to do something, for example run tests, tell the user.
-- If there are natural next steps the user may want to take, suggest them at the end of your response. Do not make suggestions if there are no natural next steps. When suggesting multiple options, use numeric lists for the suggestions so the user can quickly respond with a single number.
+- If there are natural next steps the user may want to take, suggest them at the end of your response. Do not make suggestions if there are no natural next steps.
 
-# General
-
-- When searching for text or files, prefer using `rg` or `rg --files` respectively because `rg` is much faster than alternatives like `grep`. (If the `rg` command is not found, then use alternatives.)
-
-## Editing constraints
+# Code style
 
+- Follow the precedence rules user instructions > system / dev / user / AGENTS.md instructions > match local file conventions > instructions below.
+- Use language-appropriate best practices.
+- Optimize for clarity, readability, and maintainability.
+- Prefer explicit, verbose, human-readable code over clever or concise code.
+- Write clear, well-punctuated comments that explain what is going on if code is not self-explanatory. You should not add comments like "Assigns the value to the variable", but a brief comment might be useful ahead of a complex code block that the user would otherwise have to spend time parsing out. Usage of these comments should be rare.
 - Default to ASCII when editing or creating files. Only introduce non-ASCII or other Unicode characters when there is a clear justification and the file already uses them.
-- Add succinct code comments that explain what is going on if code is not self-explanatory. You should not add comments like "Assigns the value to the variable", but a brief comment might be useful ahead of a complex code block that the user would otherwise have to spend time parsing out. Usage of these comments should be rare.
-- Try to use apply_patch for single file edits, but it is fine to explore other options to make the edit if it does not work well. Do not use apply_patch for changes that are auto-generated (i.e. generating package.json or running a lint or format command like gofmt) or when scripting is more efficient (such as search and replacing a string across a codebase).
-- You may be in a dirty git worktree.
+
+# Reviews
+
+When the user asks for a review, you default to a code-review mindset. Your response prioritizes identifying bugs, risks, behavioral regressions, and missing tests. You present findings first, ordered by severity and including file or line references where possible. Open questions or assumptions follow. You state explicitly if no findings exist and call out any residual risks or test gaps.
+
+# Your environment
+
+## Using GIT
+
+- You may be working in a dirty git worktree.
     * NEVER revert existing changes you did not make unless explicitly requested, since these changes were made by the user.
     * If asked to make a commit or code edits and there are unrelated changes to your work or changes that you didn't make in those files, don't revert those changes.
     * If the changes are in files you've touched recently, you should read carefully and understand how you can work with the changes rather than reverting them.
     * If the changes are in unrelated files, just ignore them and don't revert them.
 - Do not amend a commit unless explicitly requested to do so.
-- While you are working, you might notice unexpected changes that you didn't make. If this happens, STOP IMMEDIATELY and ask the user how they would like to proceed.
-- **NEVER** use destructive commands like `git reset --hard` or `git checkout --` unless specifically requested or approved by the user.
+- While you are working, you might notice unexpected changes that you didn't make. It's likely the user made them. If this happens, STOP IMMEDIATELY and ask the user how they would like to proceed.
+- Be cautious when using git. **NEVER** use destructive commands like `git reset --hard` or `git checkout --` unless specifically requested or approved by the user.
+- You struggle using the git interactive console. **ALWAYS** prefer using non-interactive git commands.
 
-## Plan tool
+## Agents.md
 
-When using the planning tool:
-- Skip using the planning tool for straightforward tasks (roughly the easiest 25%).
-- Do not make single-step plans.
-- When you made a plan, update it after having performed one of the sub-tasks that you shared on the plan.
+- If the directory you are in has an AGENTS.md file, it is provided to you at the top, and you don't have to search for it.
+- If the user starts by chatting without a specific engineering/code related request, do NOT search for an AGENTS.md. Only do so once there is a relevant request.
 
-## Special user requests
+# Tool use
 
-- If the user makes a simple request (such as asking for the time) which you can fulfill by running a terminal command (such as `date`), you should do so.
-- When the user asks for a review, you default to a code-review mindset. Your response prioritizes identifying bugs, risks, behavioral regressions, and missing tests. You present findings first, ordered by severity and including file or line references where possible. Open questions or assumptions follow. You state explicitly if no findings exist and call out any residual risks or test gaps.
-
-## Frontend tasks
-When doing frontend design tasks, avoid collapsing into "AI slop" or safe, average-looking layouts.
-Aim for interfaces that feel intentional, bold, and a bit surprising.
-- Typography: Use expressive, purposeful fonts and avoid default stacks (Inter, Roboto, Arial, system).
-- Color & Look: Choose a clear visual direction; define CSS variables; avoid purple-on-white defaults. No purple bias or dark mode bias.
-- Motion: Use a few meaningful animations (page-load, staggered reveals) instead of generic micro-motions.
-- Background: Don't rely on flat, single-color backgrounds; use gradients, shapes, or subtle patterns to build atmosphere.
-- Overall: Avoid boilerplate layouts and interchangeable UI patterns. Vary themes, type families, and visual languages across outputs.
-- Ensure the page loads properly on both desktop and mobile
-
-Exception: If working within an existing website or design system, preserve the established patterns, structure, and visual language.
+- Unless you are otherwise instructed, prefer using `rg` or `rg --files` respectively when searching because `rg` is much faster than alternatives like `grep`. If the `rg` command is not found, then use alternatives.
+- Use the plan tool to explain to the user what you are going to do
+  - Only use it for more complex tasks, do not use it for straightforward tasks (roughly the easiest 25%).
+  - Do not make single-step plans. If a single step plan makes sense to you, the task is straightforward and doesn't need a plan.
+  - When you made a plan, update it after having performed one of the sub-tasks that you shared on the plan.
+- Try to use apply_patch for single file edits, but it is fine to explore other options to make the edit if it does not work well. Do not use apply_patch for changes that are auto-generated (i.e. generating package.json or running a lint or format command like gofmt) or when scripting is more efficient (such as search and replacing a string across a codebase).

codex-rs/core/tests/chat_completions_payload.rs

@@ -102,7 +102,7 @@ async fn run_request(input: Vec<ResponseItem>) -> Value {
         SessionSource::Exec,
         TransportManager::new(),
     )
-    .new_session();
+    .new_session(None, None);
 
     let mut prompt = Prompt::default();
     prompt.input = input;

codex-rs/core/tests/chat_completions_sse.rs

@@ -103,7 +103,7 @@ async fn run_stream_with_bytes(sse_body: &[u8]) -> Vec<ResponseEvent> {
         SessionSource::Exec,
         TransportManager::new(),
     )
-    .new_session();
+    .new_session(None, None);
 
     let mut prompt = Prompt::default();
     prompt.input = vec![ResponseItem::Message {

codex-rs/core/tests/responses_headers.rs

@@ -12,6 +12,7 @@ use codex_core::ResponseItem;
 use codex_core::TransportManager;
 use codex_core::WEB_SEARCH_ELIGIBLE_HEADER;
 use codex_core::WireApi;
+use codex_core::X_CODEX_TURN_METADATA_HEADER;
 use codex_core::models_manager::manager::ModelsManager;
 use codex_otel::OtelManager;
 use codex_protocol::ThreadId;
@@ -23,6 +24,7 @@ use core_test_support::load_default_config_for_test;
 use core_test_support::responses;
 use core_test_support::test_codex::test_codex;
 use futures::StreamExt;
+use pretty_assertions::assert_eq;
 use tempfile::TempDir;
 use wiremock::matchers::header;
 
@@ -98,7 +100,7 @@ async fn responses_stream_includes_subagent_header_on_review() {
         session_source,
         TransportManager::new(),
     )
-    .new_session();
+    .new_session(None, None);
 
     let mut prompt = Prompt::default();
     prompt.input = vec![ResponseItem::Message {
@@ -124,6 +126,101 @@ async fn responses_stream_includes_subagent_header_on_review() {
     );
 }
 
+#[tokio::test]
+async fn responses_stream_includes_turn_metadata_header_when_set() {
+    core_test_support::skip_if_no_network!();
+
+    let server = responses::start_mock_server().await;
+    let response_body = responses::sse(vec![
+        responses::ev_response_created("resp-1"),
+        responses::ev_completed("resp-1"),
+    ]);
+
+    let request_recorder = responses::mount_sse_once(&server, response_body).await;
+
+    let provider = ModelProviderInfo {
+        name: "mock".into(),
+        base_url: Some(format!("{}/v1", server.uri())),
+        env_key: None,
+        env_key_instructions: None,
+        experimental_bearer_token: None,
+        wire_api: WireApi::Responses,
+        query_params: None,
+        http_headers: None,
+        env_http_headers: None,
+        request_max_retries: Some(0),
+        stream_max_retries: Some(0),
+        stream_idle_timeout_ms: Some(5_000),
+        requires_openai_auth: false,
+        supports_websockets: false,
+    };
+
+    let codex_home = TempDir::new().expect("failed to create TempDir");
+    let mut config = load_default_config_for_test(&codex_home).await;
+    config.model_provider_id = provider.name.clone();
+    config.model_provider = provider.clone();
+    let effort = config.model_reasoning_effort;
+    let summary = config.model_reasoning_summary;
+    let model = ModelsManager::get_model_offline(config.model.as_deref());
+    config.model = Some(model.clone());
+    let config = Arc::new(config);
+
+    let conversation_id = ThreadId::new();
+    let auth_mode = AuthMode::Chatgpt;
+    let session_source = SessionSource::SubAgent(SubAgentSource::Review);
+    let model_info = ModelsManager::construct_model_info_offline(model.as_str(), &config);
+    let otel_manager = OtelManager::new(
+        conversation_id,
+        model.as_str(),
+        model_info.slug.as_str(),
+        None,
+        Some("test@test.com".to_string()),
+        Some(auth_mode),
+        false,
+        "test".to_string(),
+        session_source.clone(),
+    );
+
+    let turn_metadata =
+        r#"{"workspaces":{"/repo":{"latest_git_commit_hash":"abc123"}}}"#.to_string();
+    let mut client_session = ModelClient::new(
+        Arc::clone(&config),
+        None,
+        model_info,
+        otel_manager,
+        provider,
+        effort,
+        summary,
+        conversation_id,
+        session_source,
+        TransportManager::new(),
+    )
+    .new_session_with_turn_metadata(Some(turn_metadata.clone()));
+
+    let mut prompt = Prompt::default();
+    prompt.input = vec![ResponseItem::Message {
+        id: None,
+        role: "user".into(),
+        content: vec![ContentItem::InputText {
+            text: "hello".into(),
+        }],
+        end_turn: None,
+    }];
+
+    let mut stream = client_session.stream(&prompt).await.expect("stream failed");
+    while let Some(event) = stream.next().await {
+        if matches!(event, Ok(ResponseEvent::Completed { .. })) {
+            break;
+        }
+    }
+
+    let request = request_recorder.single_request();
+    assert_eq!(
+        request.header(X_CODEX_TURN_METADATA_HEADER).as_deref(),
+        Some(turn_metadata.as_str())
+    );
+}
+
 #[tokio::test]
 async fn responses_stream_includes_subagent_header_on_other() {
     core_test_support::skip_if_no_network!();
@@ -197,7 +294,7 @@ async fn responses_stream_includes_subagent_header_on_other() {
         session_source,
         TransportManager::new(),
     )
-    .new_session();
+    .new_session(None, None);
 
     let mut prompt = Prompt::default();
     prompt.input = vec![ResponseItem::Message {
@@ -354,7 +451,7 @@ async fn responses_respects_model_info_overrides_from_config() {
         session_source,
         TransportManager::new(),
     )
-    .new_session();
+    .new_session(None, None);
 
     let mut prompt = Prompt::default();
     prompt.input = vec![ResponseItem::Message {

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

@@ -1190,7 +1190,7 @@ async fn azure_responses_request_includes_store_and_reasoning_ids() {
         SessionSource::Exec,
         TransportManager::new(),
     )
-    .new_session();
+    .new_session(None, None);
 
     let mut prompt = Prompt::default();
     prompt.input.push(ResponseItem::Reasoning {

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

@@ -53,7 +53,7 @@ async fn responses_websocket_streams_request() {
     .await;
 
     let harness = websocket_harness(&server).await;
-    let mut session = harness.client.new_session();
+    let mut session = harness.client.new_session(None, None);
     let prompt = prompt_with_input(vec![message_item("hello")]);
 
     stream_until_complete(&mut session, &prompt).await;
@@ -83,7 +83,7 @@ async fn responses_websocket_emits_websocket_telemetry_events() {
 
     let harness = websocket_harness(&server).await;
     harness.otel_manager.reset_runtime_metrics();
-    let mut session = harness.client.new_session();
+    let mut session = harness.client.new_session(None, None);
     let prompt = prompt_with_input(vec![message_item("hello")]);
 
     stream_until_complete(&mut session, &prompt).await;
@@ -113,7 +113,7 @@ async fn responses_websocket_emits_reasoning_included_event() {
     .await;
 
     let harness = websocket_harness(&server).await;
-    let mut session = harness.client.new_session();
+    let mut session = harness.client.new_session(None, None);
     let prompt = prompt_with_input(vec![message_item("hello")]);
 
     let mut stream = session
@@ -147,7 +147,7 @@ async fn responses_websocket_appends_on_prefix() {
     .await;
 
     let harness = websocket_harness(&server).await;
-    let mut session = harness.client.new_session();
+    let mut session = harness.client.new_session(None, None);
     let prompt_one = prompt_with_input(vec![message_item("hello")]);
     let prompt_two = prompt_with_input(vec![message_item("hello"), message_item("second")]);
 
@@ -183,7 +183,7 @@ async fn responses_websocket_creates_on_non_prefix() {
     .await;
 
     let harness = websocket_harness(&server).await;
-    let mut session = harness.client.new_session();
+    let mut session = harness.client.new_session(None, None);
     let prompt_one = prompt_with_input(vec![message_item("hello")]);
     let prompt_two = prompt_with_input(vec![message_item("different")]);