diff --git a/crates/aura-engine/src/lib.rs b/crates/aura-engine/src/lib.rs
index 34cafb7..2331dda 100644
--- a/crates/aura-engine/src/lib.rs
+++ b/crates/aura-engine/src/lib.rs
@@ -22,14 +22,20 @@
 //!   pip-equity + exposure streams into [`RunMetrics`]; [`f64_field`] bridges a
 //!   recording sink's `Vec<Scalar>` rows to it.
 //!
-//! Still to come (subsequent cycles): the broker-independent
-//! position-event output and downstream broker nodes (C10), and the param
-//! injection + orchestration axes of the atomic sim unit
-//! (`(topology + params + data-window + seed)`, swept by optimize / walk-forward
-//! / Monte-Carlo). The **seed** axis now ships: [`SyntheticSpec`] is a seeded
-//! `Source` producer (`Fn(u64) -> impl Source`, C12 seed-as-input) whose stream
-//! is fully seed-determined, making [`RunManifest`]'s seed a live captured input;
-//! the atomic unit's `-> metrics` reduction ships via [`summarize`].
+//! Orchestration families of the atomic sim unit
+//! (`(topology + params + data-window + seed)`) ship along two of C12's axes: the
+//! **grid** axis via [`sweep`] over a [`GridSpace`] into a [`SweepFamily`], and
+//! the **seed** axis via [`monte_carlo`] over a seed set into an [`McFamily`]
+//! (C12 axis 4: Monte-Carlo *is* a sweep over seeds; both drive one shared
+//! disjoint-parallel executor). The **seed** input itself ships too:
+//! [`SyntheticSpec`] is a seeded `Source` producer (`Fn(u64) -> impl Source`,
+//! C12 seed-as-input) whose stream is fully seed-determined, making
+//! [`RunManifest`]'s seed a live captured input; the atomic unit's `-> metrics`
+//! reduction ships via [`summarize`].
+//!
+//! Still to come (subsequent cycles): the broker-independent position-event
+//! output and downstream broker nodes (C10), the random param-sweep and
+//! walk-forward orchestration axes, and registry lineage across a family.
 //!
 //! Visualization is never here: it is a downstream consumer node on the streams.