Show plugin hooks in plugin details (#21447)

Supersedes the abandoned #19859, rebuilt on latest `main`.

# Why

PR #19705 adds discovery for hooks bundled with plugins, but `/plugins`
still only shows skills, apps, and MCP servers. This follow-up makes
bundled hooks visible in the same plugin detail view so users can
inspect the full plugin surface in one place.

We also need `PluginHookSummary` to populate Plugin Hooks in the app;
`hooks/list` is not enough there because plugin detail needs to show
hooks for disabled plugins too.

# What

- extend `plugin/read` with `PluginHookSummary` entries for bundled
hooks
- summarize plugin hooks while loading plugin details
- render a `Hooks` row in the `/plugins` detail popup

<img width="3456" height="848" alt="CleanShot 2026-04-27 at 11 45 34@2x"
src="https://github.com/user-attachments/assets/fe3a38d6-a260-4351-8513-fb04c93d725b"
/>

Author: abhinav-oai

codex-rs/Cargo.lock

@@ -552,10 +552,19 @@ pub struct PluginDetail {
     pub summary: PluginSummary,
     pub description: Option<String>,
     pub skills: Vec<SkillSummary>,
+    pub hooks: Vec<PluginHookSummary>,
     pub apps: Vec<AppSummary>,
     pub mcp_servers: Vec<String>,
 }
 
+#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]
+#[serde(rename_all = "camelCase")]
+#[ts(export_to = "v2/")]
+pub struct PluginHookSummary {
+    pub key: String,
+    pub event_name: HookEventName,
+}
+
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json

@@ -208,7 +208,7 @@ Example with notification opt-out:
 - `marketplace/remove` — remove a configured marketplace by name from the user marketplace config, and delete its installed marketplace root when one exists.
 - `marketplace/upgrade` — upgrade all configured Git plugin marketplaces, or one named marketplace when `marketplaceName` is provided. Returns selected marketplace names, upgraded roots, and per-marketplace errors.
 - `plugin/list` — list discovered plugin marketplaces and plugin state, including effective marketplace install/auth policy metadata, plugin `availability` (`AVAILABLE` by default or `DISABLED_BY_ADMIN` for remote plugins blocked upstream), fail-open `marketplaceLoadErrors` entries for marketplace files that could not be parsed or loaded, and best-effort `featuredPluginIds` for the official curated marketplace. `interface.category` uses the marketplace category when present; otherwise it falls back to the plugin manifest category (**under development; do not call from production clients yet**).
-- `plugin/read` — read one plugin by `marketplacePath` plus `pluginName`, returning marketplace info, a list-style `summary`, manifest descriptions/interface metadata, and bundled skills/apps/MCP server names. Returned plugin skills include their current `enabled` state after local config filtering. Plugin app summaries also include `needsAuth` when the server can determine connector accessibility (**under development; do not call from production clients yet**).
+- `plugin/read` — read one plugin by `marketplacePath` plus `pluginName`, returning marketplace info, a list-style `summary`, manifest descriptions/interface metadata, and bundled skills/hooks/apps/MCP server names. Returned plugin skills include their current `enabled` state after local config filtering; bundled hooks are returned as lightweight declaration summaries keyed for correlation with `hooks/list`. Plugin app summaries also include `needsAuth` when the server can determine connector accessibility (**under development; do not call from production clients yet**).
 - `plugin/skill/read` — read remote plugin skill markdown on demand by `remoteMarketplaceName`, `remotePluginId`, and `skillName`. This lets clients preview uninstalled remote plugin skills without downloading the plugin bundle.
 - `skills/changed` — notification emitted when watched local skill files change.
 - `app/list` — list available apps.

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json

@@ -615,6 +615,15 @@ impl PluginRequestProcessor {
                         &visible_skills,
                         &outcome.plugin.disabled_skill_paths,
                     ),
+                    hooks: outcome
+                        .plugin
+                        .hooks
+                        .into_iter()
+                        .map(|hook| codex_app_server_protocol::PluginHookSummary {
+                            key: hook.key,
+                            event_name: hook.event_name.into(),
+                        })
+                        .collect(),
                     apps: app_summaries,
                     mcp_servers: outcome.plugin.mcp_server_names,
                 }
@@ -1490,6 +1499,7 @@ fn remote_plugin_detail_to_info(
                 enabled: skill.enabled,
             })
             .collect(),
+        hooks: Vec::new(),
         apps,
         mcp_servers: Vec::new(),
     }