diff --git a/dist/npm.js b/dist/npm.js
index 7f41e8f..ec193f9 100644
--- a/dist/npm.js
+++ b/dist/npm.js
@@ -1553,7 +1553,7 @@ function npmInstall(pkgSpec, registry, inDir) {
 function npmPack(pkgSpec, registry, inDir) {
   return __async(this, null, function* () {
     const registryPrefix = pkgSpec.startsWith("@") ? `${pkgSpec.split("/")[0]}:` : "";
-    const cmdArgs = ["pack", `${pkgSpec}`, "--json", `--${registryPrefix}registry=${registry}`];
+    const cmdArgs = ["pack", `--${registryPrefix}registry=${registry}`];
     const cmdOutput = yield exec.getExecOutput("npm", cmdArgs, { cwd: inDir });
     return cmdOutput.stdout.trim().split(/\s+/).pop();
   });
diff --git a/packages/npm/src/utils.ts b/packages/npm/src/utils.ts
index 902015d..fba839e 100644
--- a/packages/npm/src/utils.ts
+++ b/packages/npm/src/utils.ts
@@ -50,7 +50,7 @@ export async function npmInstall(pkgSpec: string, registry: string, inDir?: stri
 
 export async function npmPack(pkgSpec: string, registry: string, inDir?: string): Promise<string> {
     const registryPrefix = pkgSpec.startsWith("@") ? `${pkgSpec.split("/")[0]}:` : "";
-    const cmdArgs = ["pack", `${pkgSpec}`, "--json", `--${registryPrefix}registry=${registry}`];
+    const cmdArgs = ["pack", `--${registryPrefix}registry=${registry}`];
     const cmdOutput = await exec.getExecOutput("npm", cmdArgs, { cwd: inDir });
     return cmdOutput.stdout.trim().split(/\s+/).pop() as string;
 }