1 files changed, 11 insertions, 0 deletions
diff --git a/README.md b/README.md
index 3b2d453..4350f26 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,17 @@ Use it in your workflow like this:
 `x64` is the default value for the `arch` parameter and can be omitted.
 Use `x86` if you want to build 32-bit binaries.
 
+API
+---
+
+| Input | Value | Default | Description
+| ----- | ----- | ------- | -----------
+| arch  | x64   | Yes     | Build 64-bit executables.
+|       | x86   | No      | Build 32-bit executables.
+
+The action passes the environment variables set by one of the vcvars*.bat
+scripts to the calling job.
+
 License
 -------