diff --git a/codex-rs/Cargo.lock b/codex-rs/Cargo.lock
index 4a1718c8b9..49e3c44e42 100644
--- a/codex-rs/Cargo.lock
+++ b/codex-rs/Cargo.lock
@@ -1926,6 +1926,7 @@ dependencies = [
  "codex-utils-image",
  "codex-utils-output-truncation",
  "codex-utils-path",
+ "codex-utils-plugins",
  "codex-utils-pty",
  "codex-utils-readiness",
  "codex-utils-stream-parser",
@@ -2004,10 +2005,10 @@ dependencies = [
  "codex-instructions",
  "codex-login",
  "codex-otel",
- "codex-plugin",
  "codex-protocol",
  "codex-skills",
  "codex-utils-absolute-path",
+ "codex-utils-plugins",
  "dirs",
  "dunce",
  "pretty_assertions",
@@ -2449,9 +2450,9 @@ name = "codex-plugin"
 version = "0.0.0"
 dependencies = [
  "codex-utils-absolute-path",
+ "codex-utils-plugins",
  "serde",
  "serde_json",
- "tempfile",
  "thiserror 2.0.18",
 ]
 
@@ -3009,6 +3010,15 @@ dependencies = [
  "tempfile",
 ]
 
+[[package]]
+name = "codex-utils-plugins"
+version = "0.0.0"
+dependencies = [
+ "serde",
+ "serde_json",
+ "tempfile",
+]
+
 [[package]]
 name = "codex-utils-pty"
 version = "0.0.0"
diff --git a/codex-rs/Cargo.toml b/codex-rs/Cargo.toml
index 97e520e320..0b47afb2ea 100644
--- a/codex-rs/Cargo.toml
+++ b/codex-rs/Cargo.toml
@@ -71,6 +71,7 @@ members = [
     "utils/oss",
     "utils/output-truncation",
     "utils/path-utils",
+    "utils/plugins",
     "utils/fuzzy-match",
     "utils/stream-parser",
     "codex-client",
@@ -168,6 +169,7 @@ codex-utils-json-to-toml = { path = "utils/json-to-toml" }
 codex-utils-oss = { path = "utils/oss" }
 codex-utils-output-truncation = { path = "utils/output-truncation" }
 codex-utils-path = { path = "utils/path-utils" }
+codex-utils-plugins = { path = "utils/plugins" }
 codex-utils-pty = { path = "utils/pty" }
 codex-utils-readiness = { path = "utils/readiness" }
 codex-utils-rustls-provider = { path = "utils/rustls-provider" }
diff --git a/codex-rs/core-skills/Cargo.toml b/codex-rs/core-skills/Cargo.toml
index 816f5e4483..d5e118c52a 100644
--- a/codex-rs/core-skills/Cargo.toml
+++ b/codex-rs/core-skills/Cargo.toml
@@ -20,10 +20,10 @@ codex-config = { workspace = true }
 codex-instructions = { workspace = true }
 codex-login = { workspace = true }
 codex-otel = { workspace = true }
-codex-plugin = { workspace = true }
 codex-protocol = { workspace = true }
 codex-skills = { workspace = true }
 codex-utils-absolute-path = { workspace = true }
+codex-utils-plugins = { workspace = true }
 dirs = { workspace = true }
 dunce = { workspace = true }
 reqwest = { workspace = true, features = ["json", "stream"] }
diff --git a/codex-rs/core-skills/src/skills/injection.rs b/codex-rs/core-skills/src/skills/injection.rs
index 09dc947ff5..4cfb27f963 100644
--- a/codex-rs/core-skills/src/skills/injection.rs
+++ b/codex-rs/core-skills/src/skills/injection.rs
@@ -10,7 +10,7 @@ use codex_analytics::SkillInvocation;
 use codex_analytics::TrackEventsContext;
 use codex_instructions::SkillInstructions;
 use codex_otel::SessionTelemetry;
-use codex_plugin::mention_syntax::TOOL_MENTION_SIGIL;
+use codex_utils_plugins::mention_syntax::TOOL_MENTION_SIGIL;
 use codex_protocol::models::ResponseItem;
 use codex_protocol::user_input::UserInput;
 use tokio::fs;
diff --git a/codex-rs/core-skills/src/skills/loader.rs b/codex-rs/core-skills/src/skills/loader.rs
index b671a668cf..7e5fd19a08 100644
--- a/codex-rs/core-skills/src/skills/loader.rs
+++ b/codex-rs/core-skills/src/skills/loader.rs
@@ -13,7 +13,7 @@ use codex_config::ConfigLayerStackOrdering;
 use codex_config::default_project_root_markers;
 use codex_config::merge_toml_values;
 use codex_config::project_root_markers_from_config;
-use codex_plugin::plugin_namespace_for_skill_path;
+use codex_utils_plugins::plugin_namespace_for_skill_path;
 use codex_protocol::models::FileSystemPermissions;
 use codex_protocol::models::MacOsSeatbeltProfileExtensions;
 use codex_protocol::models::NetworkPermissions;
diff --git a/codex-rs/core/Cargo.toml b/codex-rs/core/Cargo.toml
index 6727f985d7..55ce9bfb16 100644
--- a/codex-rs/core/Cargo.toml
+++ b/codex-rs/core/Cargo.toml
@@ -61,6 +61,7 @@ codex-utils-image = { workspace = true }
 codex-utils-home-dir = { workspace = true }
 codex-utils-output-truncation = { workspace = true }
 codex-utils-path = { workspace = true }
+codex-utils-plugins = { workspace = true }
 codex-utils-pty = { workspace = true }
 codex-utils-readiness = { workspace = true }
 codex-secrets = { workspace = true }
diff --git a/codex-rs/core/src/mention_syntax.rs b/codex-rs/core/src/mention_syntax.rs
index 48bfb99eca..690cd1a2f5 100644
--- a/codex-rs/core/src/mention_syntax.rs
+++ b/codex-rs/core/src/mention_syntax.rs
@@ -1,2 +1,2 @@
-pub use codex_plugin::mention_syntax::PLUGIN_TEXT_MENTION_SIGIL;
-pub use codex_plugin::mention_syntax::TOOL_MENTION_SIGIL;
+pub use codex_utils_plugins::mention_syntax::PLUGIN_TEXT_MENTION_SIGIL;
+pub use codex_utils_plugins::mention_syntax::TOOL_MENTION_SIGIL;
diff --git a/codex-rs/core/src/plugins/manifest.rs b/codex-rs/core/src/plugins/manifest.rs
index 0df4613719..6ccc6e239b 100644
--- a/codex-rs/core/src/plugins/manifest.rs
+++ b/codex-rs/core/src/plugins/manifest.rs
@@ -1,4 +1,4 @@
-use codex_plugin::PLUGIN_MANIFEST_PATH;
+use codex_utils_plugins::PLUGIN_MANIFEST_PATH;
 use codex_utils_absolute_path::AbsolutePathBuf;
 use serde::Deserialize;
 use serde_json::Value as JsonValue;
diff --git a/codex-rs/core/src/plugins/store.rs b/codex-rs/core/src/plugins/store.rs
index 2020863809..b6cd7f6803 100644
--- a/codex-rs/core/src/plugins/store.rs
+++ b/codex-rs/core/src/plugins/store.rs
@@ -1,5 +1,5 @@
 use super::load_plugin_manifest;
-use codex_plugin::PLUGIN_MANIFEST_PATH;
+use codex_utils_plugins::PLUGIN_MANIFEST_PATH;
 use codex_plugin::PluginId;
 use codex_plugin::validate_plugin_segment;
 use codex_utils_absolute_path::AbsolutePathBuf;
diff --git a/codex-rs/plugin/Cargo.toml b/codex-rs/plugin/Cargo.toml
index 339e04d278..3bffeae066 100644
--- a/codex-rs/plugin/Cargo.toml
+++ b/codex-rs/plugin/Cargo.toml
@@ -14,9 +14,8 @@ workspace = true
 
 [dependencies]
 codex-utils-absolute-path = { workspace = true }
+codex-utils-plugins = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
 serde_json = { workspace = true }
 thiserror = { workspace = true }
 
-[dev-dependencies]
-tempfile = { workspace = true }
diff --git a/codex-rs/plugin/src/lib.rs b/codex-rs/plugin/src/lib.rs
index c387044365..ae3eae7d9f 100644
--- a/codex-rs/plugin/src/lib.rs
+++ b/codex-rs/plugin/src/lib.rs
@@ -1,10 +1,11 @@
 //! Shared plugin identifiers and telemetry-facing summaries.
 
-pub mod mention_syntax;
+pub use codex_utils_plugins::mention_syntax;
+pub use codex_utils_plugins::PLUGIN_MANIFEST_PATH;
+pub use codex_utils_plugins::plugin_namespace_for_skill_path;
 
 mod load_outcome;
 mod plugin_id;
-mod plugin_namespace;
 
 pub use load_outcome::EffectiveSkillRoots;
 pub use load_outcome::LoadedPlugin;
@@ -13,8 +14,6 @@ pub use load_outcome::prompt_safe_plugin_description;
 pub use plugin_id::PluginId;
 pub use plugin_id::PluginIdError;
 pub use plugin_id::validate_plugin_segment;
-pub use plugin_namespace::PLUGIN_MANIFEST_PATH;
-pub use plugin_namespace::plugin_namespace_for_skill_path;
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct AppConnectorId(pub String);
diff --git a/codex-rs/plugin/src/mention_syntax.rs b/codex-rs/plugin/src/mention_syntax.rs
deleted file mode 100644
index de5d1432b9..0000000000
--- a/codex-rs/plugin/src/mention_syntax.rs
+++ /dev/null
@@ -1,7 +0,0 @@
-//! Sigils for tool/plugin mentions in plaintext (shared across Codex crates).
-
-/// Default plaintext sigil for tools.
-pub const TOOL_MENTION_SIGIL: char = '$';
-
-/// Plugins use `@` in linked plaintext outside TUI.
-pub const PLUGIN_TEXT_MENTION_SIGIL: char = '@';
diff --git a/codex-rs/plugin/src/plugin_namespace.rs b/codex-rs/plugin/src/plugin_namespace.rs
deleted file mode 100644
index 6688ae0469..0000000000
--- a/codex-rs/plugin/src/plugin_namespace.rs
+++ /dev/null
@@ -1,70 +0,0 @@
-//! Resolve plugin namespace from skill file paths by walking ancestors for `plugin.json`.
-
-use std::fs;
-use std::path::Path;
-
-/// Relative path from a plugin root to its manifest file.
-pub const PLUGIN_MANIFEST_PATH: &str = ".codex-plugin/plugin.json";
-
-#[derive(serde::Deserialize)]
-#[serde(rename_all = "camelCase")]
-struct RawPluginManifestName {
-    #[serde(default)]
-    name: String,
-}
-
-fn plugin_manifest_name(plugin_root: &Path) -> Option<String> {
-    let manifest_path = plugin_root.join(PLUGIN_MANIFEST_PATH);
-    if !manifest_path.is_file() {
-        return None;
-    }
-    let contents = fs::read_to_string(&manifest_path).ok()?;
-    let RawPluginManifestName { name: raw_name } = serde_json::from_str(&contents).ok()?;
-    Some(
-        plugin_root
-            .file_name()
-            .and_then(|entry| entry.to_str())
-            .filter(|_| raw_name.trim().is_empty())
-            .unwrap_or(raw_name.as_str())
-            .to_string(),
-    )
-}
-
-/// Returns the plugin manifest `name` for the nearest ancestor of `path` that contains a valid
-/// plugin manifest (same `name` rules as full manifest loading in codex-core).
-pub fn plugin_namespace_for_skill_path(path: &Path) -> Option<String> {
-    for ancestor in path.ancestors() {
-        if let Some(name) = plugin_manifest_name(ancestor) {
-            return Some(name);
-        }
-    }
-    None
-}
-
-#[cfg(test)]
-mod tests {
-    use super::plugin_namespace_for_skill_path;
-    use std::fs;
-    use tempfile::tempdir;
-
-    #[test]
-    fn uses_manifest_name() {
-        let tmp = tempdir().expect("tempdir");
-        let plugin_root = tmp.path().join("plugins/sample");
-        let skill_path = plugin_root.join("skills/search/SKILL.md");
-
-        fs::create_dir_all(skill_path.parent().expect("parent")).expect("mkdir");
-        fs::create_dir_all(plugin_root.join(".codex-plugin")).expect("mkdir manifest");
-        fs::write(
-            plugin_root.join(".codex-plugin/plugin.json"),
-            r#"{"name":"sample"}"#,
-        )
-        .expect("write manifest");
-        fs::write(&skill_path, "---\ndescription: search\n---\n").expect("write skill");
-
-        assert_eq!(
-            plugin_namespace_for_skill_path(&skill_path),
-            Some("sample".to_string())
-        );
-    }
-}