update docs

Author: esilverm

docs/source/define-tools.mdx

@@ -156,6 +156,7 @@ Both the `introspect` and `search` tools support minification of their results t
 
 - **Type prefixes**: `T=type`, `I=input`, `E=enum`, `U=union`, `F=interface`
 - **Scalar abbreviations**: `s=String`, `i=Int`, `f=Float`, `b=Boolean`, `d=ID`
+- **Directive abbreviations**: `@D=deprecated`
 - **Type modifiers**: `!=required`, `[]=list`, `<>=implements`
 
 Example comparison: