missing docs

src/modules/mod.rs

@@ -1,3 +1,17 @@
+//! Waybar module implementations.
+//!
+//! Each submodule exposes a [`WaybarModule`] type (CPU, network, audio, …)
+//! and is feature-gated by a `mod-<kind>` flag. The [`WaybarModule`] trait is
+//! what [`crate::registry::dispatch`] uses to evaluate a module on demand.
+//!
+//! Modules come in two flavours:
+//!
+//! * **Watched** — the daemon spawns a background polling/event task that
+//!   pushes state into a `watch::Receiver`, which the module reads lock-free
+//!   (network, cpu, audio, bluetooth, …).
+//! * **Dispatch-only** — evaluated on demand only, without a watch channel
+//!   (power, game, btrfs).
+
 #[cfg(feature = "mod-audio")]
 pub mod audio;
 #[cfg(feature = "mod-dbus")]
@@ -36,7 +50,14 @@ use crate::error::Result as FluxoResult;
 use crate::output::WaybarOutput;
 use crate::state::AppReceivers;
 
+/// Common interface implemented by every Waybar module.
+///
+/// Given the current daemon config, the shared state receivers, and any
+/// caller-supplied arguments, a module produces a single [`WaybarOutput`].
+/// Implementations must be cheap to evaluate — they are invoked on every
+/// client request and on every signaler state change.
 pub trait WaybarModule {
+    /// Evaluate the module and return its rendered output.
     fn run(
         &self,
         config: &Config,