fn strip_tagged_block(text: &str, open_tag: &str, close_tag: &str) -> String {

let mut result = text.to_string();

while let Some(start) = result.find(open_tag) {

if let Some(end) = result[start..].find(close_tag) {

let end_pos = start + end + close_tag.len();

result = format!("{}{}", &result[..start], &result[end_pos..]);

} else {

result = result[..start].to_string();

break;

}

}

result

}

fn strip_system_reminders(text: &str) -> String {

strip_tagged_block(text, "<system-reminder>", "</system-reminder>")

.trim()

.to_string()

}

fn strip_agents_instruction_block(text: &str) -> String {

let mut result = text.to_string();

loop {

let agents_start = result

.find("# AGENTS.md instructions for ")

.or_else(|| result.find("# agents.md instructions for "));

let Some(start) = agents_start else {

break;

};

if let Some(end) = result[start..].find("</INSTRUCTIONS>") {

let end_pos = start + end + "</INSTRUCTIONS>".len();

result = format!("{}{}", &result[..start], &result[end_pos..]);

} else {

result = result[..start].to_string();

break;

}

}

result

}

fn truncate_before_heading(text: &str, heading: &str) -> String {

let mut offset = 0usize;

for line in text.lines() {

if line.trim_start().starts_with(heading) {

return text[..offset].trim().to_string();

}

offset += line.len();

if offset < text.len() {

offset += 1;

}

}

text.trim().to_string()

}

fn collapse_blank_lines(text: &str) -> String {

let mut out = String::new();

let mut saw_blank = false;

for line in text.lines() {

let trimmed = line.trim_end();

if trimmed.trim().is_empty() {

if saw_blank || out.is_empty() {

continue;

}

saw_blank = true;

out.push('\n');

continue;

}

if !out.is_empty() && !out.ends_with('\n') {

out.push('\n');

}

out.push_str(trimmed);

out.push('\n');

saw_blank = false;

}

out.trim().to_string()

}

pub(crate) fn sanitize_codex_memory_rollout_text(text: &str) -> Option<String> {

let mut cleaned = strip_system_reminders(text);

cleaned = strip_agents_instruction_block(&cleaned);

cleaned = strip_tagged_block(&cleaned, "<skill>", "</skill>");

cleaned = collapse_blank_lines(&cleaned);

let trimmed = cleaned.trim();

if trimmed.is_empty() {

return None;

}

Some(trimmed.to_string())

}

pub(crate) fn sanitize_codex_query_text(text: &str) -> Option<String> {

let mut cleaned = sanitize_codex_memory_rollout_text(text)?;

cleaned = strip_tagged_block(&cleaned, "<environment_context>", "</environment_context>");

cleaned = strip_tagged_block(

&cleaned,

"<permissions instructions>",

"</permissions instructions>",

);

cleaned = strip_tagged_block(&cleaned, "<collaboration_mode>", "</collaboration_mode>");

cleaned = strip_tagged_block(

&cleaned,

"<subagent_notification>",

"</subagent_notification>",

);

cleaned = truncate_before_heading(&cleaned, "Workflow context:");

cleaned = truncate_before_heading(&cleaned, "Start by checking:");

cleaned = truncate_before_heading(&cleaned, "Designer stack notes:");

cleaned = collapse_blank_lines(&cleaned);

let trimmed = cleaned.trim();

if trimmed.is_empty()

|| trimmed.starts_with("<environment_context>")

|| trimmed.starts_with("<INSTRUCTIONS>")

|| trimmed.starts_with("# AGENTS.md instructions")

|| trimmed.starts_with("# agents.md instructions")

{

return None;

}

Some(trimmed.to_string())

}

#[cfg(test)]

mod tests {

use super::{sanitize_codex_memory_rollout_text, sanitize_codex_query_text};

#[test]

fn rollout_sanitizer_drops_agents_and_skills_but_keeps_environment() {

let text = concat!(

"# AGENTS.md instructions for /tmp\n\n",

"<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>\n",

"<environment_context>\n<cwd>/tmp</cwd>\n</environment_context>\n",

"<skill>\n<name>demo</name>\nbody\n</skill>\n",

"<subagent_notification>{\"agent_id\":\"a\",\"status\":\"completed\"}</subagent_notification>\n"

);

let cleaned = sanitize_codex_memory_rollout_text(text).expect("cleaned");

assert!(!cleaned.contains("AGENTS.md"));

assert!(!cleaned.contains("<skill>"));

assert!(cleaned.contains("<environment_context>"));

assert!(cleaned.contains("<subagent_notification>"));

}

#[test]

fn query_sanitizer_keeps_only_real_user_intent() {

let text = concat!(

"# AGENTS.md instructions for /tmp\n\n",

"<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>\n",

"<environment_context>\n<cwd>/tmp</cwd>\n</environment_context>\n",

"write plan for rollout\n\n",

"Workflow context:\n- Repo: ~/code/example\n"

);

assert_eq!(

sanitize_codex_query_text(text).as_deref(),

Some("write plan for rollout")

);

}

#[test]

fn query_sanitizer_drops_context_only_messages() {

let text = concat!(

"# AGENTS.md instructions for /tmp\n\n",

"<INSTRUCTIONS>\nbody\n</INSTRUCTIONS>\n",

"<environment_context>\n<cwd>/tmp</cwd>\n</environment_context>\n"

);

assert_eq!(sanitize_codex_query_text(text), None);

}

}