chore(skills) Update skills guidance

codex-rs/core/src/project_doc.rs

@@ -237,6 +237,7 @@ mod tests {
     use super::*;
     use crate::config::ConfigBuilder;
     use crate::skills::load_skills;
+    use crate::skills::render::HOW_TO_USE_SKILLS;
     use std::fs;
     use std::path::PathBuf;
     use tempfile::TempDir;
@@ -516,9 +517,8 @@ mod tests {
         )
         .unwrap_or_else(|_| cfg.codex_home.join("skills/pdf-processing/SKILL.md"));
         let expected_path_str = expected_path.to_string_lossy().replace('\\', "/");
-        let usage_rules = "- Discovery: The list above is the skills available in this session (name + description + file path). Skill bodies live on disk at the listed paths.\n- Trigger rules: If the user names a skill (with `$SkillName` or plain text) OR the task clearly matches a skill's description shown above, you must use that skill for that turn. Multiple mentions mean use them all. Do not carry skills across turns unless re-mentioned.\n- Missing/blocked: If a named skill isn't in the list or the path can't be read, say so briefly and continue with the best fallback.\n- How to use a skill (progressive disclosure):\n  1) After deciding to use a skill, open its `SKILL.md`. Read only enough to follow the workflow.\n  2) If `SKILL.md` points to extra folders such as `references/`, load only the specific files needed for the request; don't bulk-load everything.\n  3) If `scripts/` exist, prefer running or patching them instead of retyping large code blocks.\n  4) If `assets/` or templates exist, reuse them instead of recreating from scratch.\n- Coordination and sequencing:\n  - If multiple skills apply, choose the minimal set that covers the request and state the order you'll use them.\n  - Announce which skill(s) you're using and why (one short line). If you skip an obvious skill, say why.\n- Context hygiene:\n  - Keep context small: summarize long sections instead of pasting them; only load extra files when needed.\n  - Avoid deep reference-chasing: prefer opening only files directly linked from `SKILL.md` unless you're blocked.\n  - When variants exist (frameworks, providers, domains), pick only the relevant reference file(s) and note that choice.\n- Safety and fallback: If a skill can't be applied cleanly (missing files, unclear instructions), state the issue, pick the next-best approach, and continue.";
         let expected = format!(
-            "base doc\n\n## Skills\nA skill is a set of local instructions to follow that is stored in a `SKILL.md` file. Below is the list of skills that can be used. Each entry includes a name, description, and file path so you can open the source for full instructions when using a specific skill.\n### Available skills\n- pdf-processing: extract from pdfs (file: {expected_path_str})\n### How to use skills\n{usage_rules}"
+            "base doc\n\n# Skills\nA skill is a set of local instructions to follow that is stored in a `SKILL.md` file. Below is the list of skills that can be used. Each entry includes a name, description, and file path so you can open the source for full instructions when using a specific skill.\n## Available skills\n- pdf-processing: extract from pdfs (file: {expected_path_str})\n{HOW_TO_USE_SKILLS}"
         );
         assert_eq!(res, expected);
     }
@@ -540,9 +540,8 @@ mod tests {
             dunce::canonicalize(cfg.codex_home.join("skills/linting/SKILL.md").as_path())
                 .unwrap_or_else(|_| cfg.codex_home.join("skills/linting/SKILL.md"));
         let expected_path_str = expected_path.to_string_lossy().replace('\\', "/");
-        let usage_rules = "- Discovery: The list above is the skills available in this session (name + description + file path). Skill bodies live on disk at the listed paths.\n- Trigger rules: If the user names a skill (with `$SkillName` or plain text) OR the task clearly matches a skill's description shown above, you must use that skill for that turn. Multiple mentions mean use them all. Do not carry skills across turns unless re-mentioned.\n- Missing/blocked: If a named skill isn't in the list or the path can't be read, say so briefly and continue with the best fallback.\n- How to use a skill (progressive disclosure):\n  1) After deciding to use a skill, open its `SKILL.md`. Read only enough to follow the workflow.\n  2) If `SKILL.md` points to extra folders such as `references/`, load only the specific files needed for the request; don't bulk-load everything.\n  3) If `scripts/` exist, prefer running or patching them instead of retyping large code blocks.\n  4) If `assets/` or templates exist, reuse them instead of recreating from scratch.\n- Coordination and sequencing:\n  - If multiple skills apply, choose the minimal set that covers the request and state the order you'll use them.\n  - Announce which skill(s) you're using and why (one short line). If you skip an obvious skill, say why.\n- Context hygiene:\n  - Keep context small: summarize long sections instead of pasting them; only load extra files when needed.\n  - Avoid deep reference-chasing: prefer opening only files directly linked from `SKILL.md` unless you're blocked.\n  - When variants exist (frameworks, providers, domains), pick only the relevant reference file(s) and note that choice.\n- Safety and fallback: If a skill can't be applied cleanly (missing files, unclear instructions), state the issue, pick the next-best approach, and continue.";
         let expected = format!(
-            "## Skills\nA skill is a set of local instructions to follow that is stored in a `SKILL.md` file. Below is the list of skills that can be used. Each entry includes a name, description, and file path so you can open the source for full instructions when using a specific skill.\n### Available skills\n- linting: run clippy (file: {expected_path_str})\n### How to use skills\n{usage_rules}"
+            "# Skills\nA skill is a set of local instructions to follow that is stored in a `SKILL.md` file. Below is the list of skills that can be used. Each entry includes a name, description, and file path so you can open the source for full instructions when using a specific skill.\n## Available skills\n- linting: run clippy (file: {expected_path_str})\n{HOW_TO_USE_SKILLS}"
         );
         assert_eq!(res, expected);
     }

codex-rs/core/src/skills/render.rs

@@ -6,9 +6,9 @@ pub fn render_skills_section(skills: &[SkillMetadata]) -> Option<String> {
     }
 
     let mut lines: Vec<String> = Vec::new();
-    lines.push("## Skills".to_string());
+    lines.push("# Skills".to_string());
     lines.push("A skill is a set of local instructions to follow that is stored in a `SKILL.md` file. Below is the list of skills that can be used. Each entry includes a name, description, and file path so you can open the source for full instructions when using a specific skill.".to_string());
-    lines.push("### Available skills".to_string());
+    lines.push("## Available skills".to_string());
 
     for skill in skills {
         let path_str = skill.path.to_string_lossy().replace('\\', "/");
@@ -17,24 +17,23 @@ pub fn render_skills_section(skills: &[SkillMetadata]) -> Option<String> {
         lines.push(format!("- {name}: {description} (file: {path_str})"));
     }
 
-    lines.push("### How to use skills".to_string());
+    lines.push("".to_string());
     lines.push(
-        r###"- Discovery: The list above is the skills available in this session (name + description + file path). Skill bodies live on disk at the listed paths.
-- Trigger rules: If the user names a skill (with `$SkillName` or plain text) OR the task clearly matches a skill's description shown above, you must use that skill for that turn. Multiple mentions mean use them all. Do not carry skills across turns unless re-mentioned.
-- Missing/blocked: If a named skill isn't in the list or the path can't be read, say so briefly and continue with the best fallback.
+        r###"## How to use skills
+- Discovery: The list above is the skills available in this session (name + description + file path). Skill bodies live on disk at the listed paths.
+- Trigger rules:
+  - If the user names a skill (with `$SkillName` or plain text) OR the task clearly matches a skill's description shown above, you should do your best to use that skill for that turn. 
+  - If the user references multiple skills, you should use them all.
+  - Do not carry skills across turns unless re-mentioned.
+- Missing/blocked on skill discovery: If a named skill isn't in the list or the path can't be read, pick a reasonable fallback and continue.
 - How to use a skill (progressive disclosure):
   1) After deciding to use a skill, open its `SKILL.md`. Read only enough to follow the workflow.
   2) If `SKILL.md` points to extra folders such as `references/`, load only the specific files needed for the request; don't bulk-load everything.
   3) If `scripts/` exist, prefer running or patching them instead of retyping large code blocks.
   4) If `assets/` or templates exist, reuse them instead of recreating from scratch.
 - Coordination and sequencing:
-  - If multiple skills apply, choose the minimal set that covers the request and state the order you'll use them.
-  - Announce which skill(s) you're using and why (one short line). If you skip an obvious skill, say why.
-- Context hygiene:
-  - Keep context small: summarize long sections instead of pasting them; only load extra files when needed.
-  - Avoid deep reference-chasing: prefer opening only files directly linked from `SKILL.md` unless you're blocked.
-  - When variants exist (frameworks, providers, domains), pick only the relevant reference file(s) and note that choice.
-- Safety and fallback: If a skill can't be applied cleanly (missing files, unclear instructions), state the issue, pick the next-best approach, and continue."###
+  - If multiple skills apply to the current task, choose the minimal set that can complete the request.
+- Safety and fallback: If a skill can't be applied cleanly (missing files, unclear instructions), pick the next-best approach, and continue."###
             .to_string(),
     );
 

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

@@ -734,7 +734,7 @@ async fn skills_append_to_instructions() {
         .as_str()
         .expect("instructions text");
     assert!(
-        instructions_text.contains("## Skills"),
+        instructions_text.contains("# Skills"),
         "expected skills section present"
     );
     assert!(