feat: Support listing and selecting skills via $ or /skills

codex-rs/core/src/project_doc.rs

@@ -516,8 +516,9 @@ 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: Available skills are listed in project docs and may also appear in a runtime \"## Skills\" section (name + description + file path). These are the sources of truth; 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, 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- Description as trigger: The YAML `description` in `SKILL.md` is the primary trigger signal; rely on it to decide applicability. If unsure, ask a brief clarification before proceeding.\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 deeply nested references; prefer one-hop files explicitly linked from `SKILL.md`.\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\nThese skills are discovered at startup from ~/.codex/skills; each entry shows name, description, and file path so you can open the source for full instructions. Content is not inlined to keep context lean.\n- pdf-processing: extract from pdfs (file: {expected_path_str})"
+            "base doc\n\n## Skills\nThese skills are discovered at startup from ~/.codex/skills; each entry shows name, description, and file path so you can open the source for full instructions. Content is not inlined to keep context lean.\n- pdf-processing: extract from pdfs (file: {expected_path_str})\n{usage_rules}"
         );
         assert_eq!(res, expected);
     }
@@ -535,8 +536,9 @@ 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: Available skills are listed in project docs and may also appear in a runtime \"## Skills\" section (name + description + file path). These are the sources of truth; 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, 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- Description as trigger: The YAML `description` in `SKILL.md` is the primary trigger signal; rely on it to decide applicability. If unsure, ask a brief clarification before proceeding.\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 deeply nested references; prefer one-hop files explicitly linked from `SKILL.md`.\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\nThese skills are discovered at startup from ~/.codex/skills; each entry shows name, description, and file path so you can open the source for full instructions. Content is not inlined to keep context lean.\n- linting: run clippy (file: {expected_path_str})"
+            "## Skills\nThese skills are discovered at startup from ~/.codex/skills; each entry shows name, description, and file path so you can open the source for full instructions. Content is not inlined to keep context lean.\n- linting: run clippy (file: {expected_path_str})\n{usage_rules}"
         );
         assert_eq!(res, expected);
     }

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

@@ -17,5 +17,26 @@ pub fn render_skills_section(skills: &[SkillMetadata]) -> Option<String> {
         ));
     }
 
+    lines.push(
+        r###"- Discovery: Available skills are listed in project docs and may also appear in a runtime "## Skills" section (name + description + file path). These are the sources of truth; 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, 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.
+- 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.
+- Description as trigger: The YAML `description` in `SKILL.md` is the primary trigger signal; rely on it to decide applicability. If unsure, ask a brief clarification before proceeding.
+- 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 deeply nested references; prefer one-hop files explicitly linked from `SKILL.md`.
+  - 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."###
+            .to_string(),
+    );
+
     Some(lines.join("\n"))
 }

codex-rs/tui/src/app.rs

@@ -25,7 +25,6 @@ use codex_core::AuthManager;
 use codex_core::ConversationManager;
 use codex_core::config::Config;
 use codex_core::config::edit::ConfigEditsBuilder;
-#[cfg(target_os = "windows")]
 use codex_core::features::Feature;
 use codex_core::model_family::find_family_for_model;
 use codex_core::openai_models::model_presets::HIDE_GPT_5_1_CODEX_MAX_MIGRATION_PROMPT_CONFIG;
@@ -37,6 +36,7 @@ use codex_core::protocol::Op;
 use codex_core::protocol::SessionSource;
 use codex_core::protocol::TokenUsage;
 use codex_core::skills::load_skills;
+use codex_core::skills::model::SkillMetadata;
 use codex_protocol::ConversationId;
 use codex_protocol::openai_models::ModelUpgrade;
 use codex_protocol::openai_models::ReasoningEffort as ReasoningEffortConfig;
@@ -231,6 +231,8 @@ pub(crate) struct App {
 
     // One-shot suppression of the next world-writable scan after user confirmation.
     skip_world_writable_scan_once: bool,
+
+    pub(crate) skills: Option<Vec<SkillMetadata>>,
 }
 
 impl App {
@@ -285,6 +287,12 @@ impl App {
             }
         }
 
+        let skills = if config.features.enabled(Feature::Skills) {
+            Some(skills_outcome.skills.clone())
+        } else {
+            None
+        };
+
         let enhanced_keys_supported = tui.enhanced_keys_supported();
 
         let mut chat_widget = match resume_selection {
@@ -298,6 +306,7 @@ impl App {
                     enhanced_keys_supported,
                     auth_manager: auth_manager.clone(),
                     feedback: feedback.clone(),
+                    skills: skills.clone(),
                     is_first_run,
                 };
                 ChatWidget::new(init, conversation_manager.clone())
@@ -322,6 +331,7 @@ impl App {
                     enhanced_keys_supported,
                     auth_manager: auth_manager.clone(),
                     feedback: feedback.clone(),
+                    skills: skills.clone(),
                     is_first_run,
                 };
                 ChatWidget::new_from_existing(
@@ -357,6 +367,7 @@ impl App {
             pending_update_action: None,
             suppress_shutdown_complete: false,
             skip_world_writable_scan_once: false,
+            skills,
         };
 
         // On startup, if Agent mode (workspace-write) or ReadOnly is active, warn about world-writable dirs on Windows.
@@ -476,6 +487,7 @@ impl App {
                     enhanced_keys_supported: self.enhanced_keys_supported,
                     auth_manager: self.auth_manager.clone(),
                     feedback: self.feedback.clone(),
+                    skills: self.skills.clone(),
                     is_first_run: false,
                 };
                 self.chat_widget = ChatWidget::new(init, self.server.clone());
@@ -523,6 +535,7 @@ impl App {
                                     enhanced_keys_supported: self.enhanced_keys_supported,
                                     auth_manager: self.auth_manager.clone(),
                                     feedback: self.feedback.clone(),
+                                    skills: self.skills.clone(),
                                     is_first_run: false,
                                 };
                                 self.chat_widget = ChatWidget::new_from_existing(
@@ -1147,6 +1160,7 @@ mod tests {
             pending_update_action: None,
             suppress_shutdown_complete: false,
             skip_world_writable_scan_once: false,
+            skills: None,
         }
     }
 
@@ -1184,6 +1198,7 @@ mod tests {
                 pending_update_action: None,
                 suppress_shutdown_complete: false,
                 skip_world_writable_scan_once: false,
+                skills: None,
             },
             rx,
             op_rx,

codex-rs/tui/src/app_backtrack.rs

@@ -347,6 +347,7 @@ impl App {
             enhanced_keys_supported: self.enhanced_keys_supported,
             auth_manager: self.auth_manager.clone(),
             feedback: self.feedback.clone(),
+            skills: self.skills.clone(),
             is_first_run: false,
         };
         self.chat_widget =