docs: prefer typed objects for closed configuration interfaces

CONTEXT.md

@@ -22,3 +22,14 @@ The presentation and input experience through which a user interacts with an edi
 
 **Capability**:
 A named frontend ability required by a feature for compatibility, not a permission granted to that feature.
+
+## Configuration interfaces
+
+- Prefer typed objects for editor-owned actions, modes, and other closed sets. Expose new core binding targets through `config.core` rather than requiring command-name strings.
+- Use strings for open-ended identifiers: language IDs, paths, and external plugin command names. Interactive Ex command names remain textual.
+- Ruby action/mode objects provide validation during configuration evaluation and discoverable members, not compile-time enum safety.
+
+```ruby
+config.bind "leader n", config.core.word_next, mode: config.modes.normal
+config.lsp["my-language"] = { command: ["my-language-server"], extensions: ["myl"] }
+```