diff --git a/src/ast/environment.rs b/src/ast/environment.rs
index 0ee3e89..188c9e5 100644
--- a/src/ast/environment.rs
+++ b/src/ast/environment.rs
@@ -21,13 +21,13 @@ use crate::ast::compiler::macros::{MacroEvaluator, MacroExpander, MacroRegistry}
 use crate::ast::compiler::optimizer::Optimizer;
 use crate::ast::compiler::specializer::{FunctionRegistry, MonoCache, RtlLookupFunc, Specializer};
 use crate::ast::rtl::{self, intrinsics};
+use crate::ast::rtl::docs::{PipelineGenerator, RtlDocEntry, RtlRegistration};
 use crate::ast::types::{
     CommentLine, NativeFunction, NodeIdentity, Purity, SourceLocation, StaticType, Value,
 };
 
 use crate::ast::diagnostics::Diagnostics;
 pub use crate::ast::compiler::CompilationResult;
-pub type PipelineGenerator = Box<dyn FnMut() -> bool>;
 
 const SYSTEM_LIB_SOURCE: &str = include_str!("rtl/prelude.myc");
 const SYSTEM_LIB_PATH: &str = "<embedded>/prelude.myc";
@@ -36,62 +36,6 @@ fn make_rtl_lookup() -> RtlLookupFunc {
     Rc::new(|name: &str, args: &[StaticType]| intrinsics::lookup(name, args))
 }
 
-/// Documentation entry for a single RTL symbol (function or constant).
-/// Populated via the builder returned by `register_native_fn` / `register_constant`.
-pub struct RtlDocEntry {
-    pub name: String,
-    /// Short one-line description (required).
-    pub one_liner: &'static str,
-    /// Optional longer explanation.
-    pub description: Option<&'static str>,
-    /// Optional Myc code examples.
-    pub examples: Option<&'static [&'static str]>,
-}
-
-/// Builder returned by `register_native_fn` and `register_constant`.
-/// Call `.doc(...)` to attach documentation; optional `.description(...)` and `.examples(...)`
-/// can be chained. The entry is written to the registry when the builder is dropped.
-pub struct RtlRegistration {
-    name: String,
-    rtl_docs: Rc<RefCell<Vec<RtlDocEntry>>>,
-    one_liner: Option<&'static str>,
-    description: Option<&'static str>,
-    examples: Option<&'static [&'static str]>,
-}
-
-impl RtlRegistration {
-    /// Attach a required one-line description.
-    pub fn doc(mut self, one_liner: &'static str) -> Self {
-        self.one_liner = Some(one_liner);
-        self
-    }
-
-    /// Attach an optional longer description (must call `.doc()` first).
-    pub fn description(mut self, desc: &'static str) -> Self {
-        self.description = Some(desc);
-        self
-    }
-
-    /// Attach optional usage examples as Myc code strings.
-    pub fn examples(mut self, ex: &'static [&'static str]) -> Self {
-        self.examples = Some(ex);
-        self
-    }
-}
-
-impl Drop for RtlRegistration {
-    fn drop(&mut self) {
-        if let Some(one_liner) = self.one_liner {
-            self.rtl_docs.borrow_mut().push(RtlDocEntry {
-                name: self.name.clone(),
-                one_liner,
-                description: self.description,
-                examples: self.examples,
-            });
-        }
-    }
-}
-
 pub struct Environment {
     pub root_types: Rc<RefCell<Vec<StaticType>>>,
     pub root_purity: Rc<RefCell<Vec<Purity>>>,
@@ -603,24 +547,12 @@ impl Environment {
                 purity: purity_level,
             }),
         );
-        RtlRegistration {
-            name: name.to_string(),
-            rtl_docs: Rc::clone(&self.rtl_docs),
-            one_liner: None,
-            description: None,
-            examples: None,
-        }
+        RtlRegistration::new(name.to_string(), Rc::clone(&self.rtl_docs))
     }
 
     pub fn register_constant(&self, name: &str, ty: StaticType, val: Value) -> RtlRegistration {
         self.allocate_slot(name, ty, Purity::Pure, val);
-        RtlRegistration {
-            name: name.to_string(),
-            rtl_docs: Rc::clone(&self.rtl_docs),
-            one_liner: None,
-            description: None,
-            examples: None,
-        }
+        RtlRegistration::new(name.to_string(), Rc::clone(&self.rtl_docs))
     }
 
 
diff --git a/src/ast/rtl/mod.rs b/src/ast/rtl/mod.rs
index a31f4a0..9802a42 100644
--- a/src/ast/rtl/mod.rs
+++ b/src/ast/rtl/mod.rs
@@ -1,11 +1,14 @@
 pub mod core;
 pub mod datetime;
+pub mod docs;
 pub mod intrinsics;
 pub mod math;
 pub mod series;
 pub mod streams;
 pub mod type_registry;
 
+pub use docs::{PipelineGenerator, RtlDocEntry, RtlRegistration};
+
 use crate::ast::environment::Environment;
 
 pub fn register(env: &Environment) {