diff --git a/.changeset/dirty-poets-swim.md b/.changeset/dirty-poets-swim.md
new file mode 100644
index 00000000..38a42fe1
--- /dev/null
+++ b/.changeset/dirty-poets-swim.md
@@ -0,0 +1,5 @@
+---
+"wrangler-action": patch
+---
+
+Fixed the package manager not being inferred based on lockfile when the `packageManager` input isn't set.
diff --git a/action.yml b/action.yml
index 657d76a9..b5fda3ea 100644
--- a/action.yml
+++ b/action.yml
@@ -42,6 +42,5 @@ inputs:
     description: "A string of environment variable names, separated by newlines. These will be bound to your Worker using the values of matching environment variables declared in `env` of this workflow."
     required: false
   packageManager:
-    description: "The package manager you'd like to use to install and run wrangler. If not specified, a value will be inferred based on the presence of a lockfile. Valid values: [npm, pnpm, yarn, bun]"
+    description: "The package manager you'd like to use to install and run wrangler. If not specified, the preferred package manager will be inferred based on the presence of a lockfile or fallback to using npm if no lockfile is found. Valid values are `npm` | `pnpm` | `yarn` | `bun`."
     required: false
-    default: npm
diff --git a/test/bun/package.json b/test/bun/package.json
index 75d5eebd..e5fb3ef1 100644
--- a/test/bun/package.json
+++ b/test/bun/package.json
@@ -1,3 +1,3 @@
 {
-  "name": "wrangler-action-bun-test",
+  "name": "wrangler-action-bun-test"
 }