diff --git a/portability.md b/portability.md
index 45ed737..4ecf8f6 100644
--- a/portability.md
+++ b/portability.md
@@ -6,7 +6,7 @@
 
 ```
 ~/Projects/standards/
-  how-i-work.md   portability.md   retrofit-playbook.md
+  how-i-work.md   portability.md   retrofit-playbook.md   subagents-handbook.md
   guides/                  ← neutral substance (vendor-agnostic): checklists, role knowledge
   adapters/
     claude/
@@ -14,7 +14,7 @@
       agents/              ← ~/.claude/agents symlinks here (global subagents)
 ```
 
-Companions: `how-i-work.md` (the always-loaded user layer, under 50 lines) and `retrofit-playbook.md` (the one-time conversion manual). This document is reference material — never symlink it into anything always-loaded.
+Companions: `how-i-work.md` (the always-loaded user layer, under 50 lines), `retrofit-playbook.md` (the one-time conversion manual), and `subagents-handbook.md` (designing and running delegated agents). This document is reference material — never symlink it into anything always-loaded.
 
 ## The principle