diff --git a/.changeset/vars-partial-parse.md b/.changeset/vars-partial-parse.md
new file mode 100644
index 0000000..1942137
--- /dev/null
+++ b/.changeset/vars-partial-parse.md
@@ -0,0 +1,5 @@
+---
+'incur': patch
+---
+
+Fixed eager `varsSchema.parse({})` throwing ZodError for required vars populated by middleware. Vars are now initialized with `varsSchema.partial().parse({})`, preserving schema defaults while allowing middleware-populated required fields.
diff --git a/src/Cli.test.ts b/src/Cli.test.ts
index 7201b57..e6fe71d 100644
--- a/src/Cli.test.ts
+++ b/src/Cli.test.ts
@@ -6099,6 +6099,25 @@ describe('globals', () => {
     expect(JSON.parse(output)).toEqual({ chain: 'mainnet' })
   })
 
+  test('required (nonoptional) vars populated by middleware do not throw pre-middleware (#188)', async () => {
+    const cli = Cli.create('test', {
+      globals: z.object({ chain: z.string().default('ethereum') }),
+      vars: z.object({ chain: z.string().nonoptional() }),
+    })
+      .use(async (c, next) => {
+        c.set('chain', c.globals.chain)
+        await next()
+      })
+      .command('ping', {
+        run(c) {
+          return { chain: c.var.chain }
+        },
+      })
+
+    const { output } = await serve(cli, ['ping', '--json'])
+    expect(JSON.parse(output)).toEqual({ chain: 'ethereum' })
+  })
+
   test('globals appear in --help output', async () => {
     const cli = Cli.create('test', {
       globals: z.object({
diff --git a/src/internal/command.ts b/src/internal/command.ts
index 7b29830..a178693 100644
--- a/src/internal/command.ts
+++ b/src/internal/command.ts
@@ -52,7 +52,7 @@ export async function execute(command: any, options: execute.Options): Promise<e
   const displayName = options.displayName ?? name
   const parseMode = options.parseMode ?? 'argv'
 
-  const varsMap: Record<string, unknown> = varsSchema ? varsSchema.parse({}) : {}
+  const varsMap: Record<string, unknown> = varsSchema ? varsSchema.partial().parse({}) : {}
   let result: execute.Result | undefined
   // For streaming with middleware: runCommand suspends on streamConsumed so middleware "after"
   // runs after the stream is consumed. The wrapped generator resolves it in its finally block.