diff --git a/doc/api/packages.md b/doc/api/packages.md
index ad487ce30b0967..2d4859b788ee41 100644
--- a/doc/api/packages.md
+++ b/doc/api/packages.md
@@ -613,6 +613,10 @@ is provided below to assist with ecosystem coordination.
 * `"types"` - can be used by typing systems to resolve the typing file for
   the given export. _This condition should always be included first._
 * `"deno"` - indicates a variation for the Deno platform.
+* `"worker"` - web workers (scripts that run in browser background threads).
+  _Must always be mutually exclusive with `"dom"`._
+* `"dom"` - browser code that uses DOM APIs. _Must always be mutually exclusive
+  with `"worker"`._
 * `"browser"` - any web browser environment.
 * `"development"` - can be used to define a development-only environment
   entry point, for example to provide additional debugging context such as