Document completion scope and gaps

AGENTS.md

@@ -120,8 +120,10 @@ Tier 3: parsed 714 files, 714 clean (100.0%), 0 with errors, 0 PsiErrorElements
   `#import`/`#load` path references with standard go-to-definition resolution.
   Headless tests cover source-ordered declarations, nested structure members,
   folding ranges, local `#load`, and Jai module directories.
-- **Phase 5** — completion, same-file and imported symbol navigation, rename,
-  and find-usages for declaration names.
+- **Phase 5** — basic completion for keywords, directives, and module/file
+  paths; same-file and imported symbol navigation; rename; and find-usages for
+  declaration names. Symbol-aware identifier/member completion remains future
+  work.
 - **Phase 5a** — persistent project settings for Jai module/import roots,
   shared root-aware resolution and completion, and indexed external Jai library
   sources. Headless tests cover state round-tripping, the Settings panel,
@@ -186,6 +188,14 @@ Tier 3: parsed 714 files, 714 clean (100.0%), 0 with errors, 0 PsiErrorElements
   `JaiReferenceHostMixin` from the BNF. Do not remove the mixin and expect a
   `PsiReferenceContributor` to be queried through the standard reference service.
 
+### Known code-insight gaps
+
+- Completion currently offers keywords, compiler directives, and module/file
+  paths, but not declarations, imported symbols, parameters, struct fields, or
+  module-qualified members.
+- Module-qualified members, procedure parameters, and struct fields also do
+  not yet have symbol resolution.
+
 ### In progress — pick up here
 
 1. **Phases 6+** — formatter, inspections, compiler integration, and other