diff --git a/test/vector-fail.rkt b/test/vector-fail.rkt
new file mode 100644
index 0000000..8e2fbc7
--- /dev/null
+++ b/test/vector-fail.rkt
@@ -0,0 +1,33 @@
+#lang racket/base
+
+(define (expr->typed-module expr)
+  #`(module t typed/racket/base
+      (require trivial/vector)
+      #,expr))
+
+(define TEST-CASE* (map expr->typed-module '(
+  (vector-ref: (vector 1) 3)
+
+  (let-vector: ([v (vector 1 2 3)])
+    (vector-ref: v 3))
+
+  (let ()
+    (define-vector: v (vector 3 4))
+    (vector-ref: v 9))
+
+)))
+
+;; -----------------------------------------------------------------------------
+
+(module+ test
+  (require
+    rackunit)
+
+  (define (vector-eval stx)
+    (lambda () ;; For `check-exn`
+      (compile-syntax stx)))
+
+  (for ([rkt (in-list TEST-CASE*)])
+    (check-exn #rx"vector::|Type Checker"
+      (vector-eval rkt)))
+)
diff --git a/test/vector-pass.rkt b/test/vector-pass.rkt
index 7dc3501..c4168fe 100644
--- a/test/vector-pass.rkt
+++ b/test/vector-pass.rkt
@@ -81,6 +81,29 @@
            Zero)
       0))
 
+  ;; -- vector-ref
+  (test-case "vector/length ref"
+    (check-equal? (vector-ref: (vector 1) 0) 1))
+
+  (test-case "vector/length ref, via let"
+    (let-vector: ([v (vector 2)])
+      (check-equal? (vector-ref: v 0) 2)))
+
+  (test-case "vector/length ref, via define"
+    (define-vector: v (vector "a" "bee" "sea"))
+    (check-equal? (vector-ref: v 2) "sea"))
+
+  (test-case "plain vector ref"
+    (check-equal?
+      ((lambda (v) (vector-ref: v 3)) (vector 8 2 19 3 0))
+      3))
+
+  (test-case "higher-order vector ref"
+    (check-exn exn:fail:contract?
+      (lambda ()
+        ((lambda ([f : (-> (Vectorof Any) Natural Any)])
+          (f (vector 0 1 2) 10)) vector-ref:))))
+
   ;; -- define-vector:
   (let ()
     (define-vector: v (vector 1 1 2 2))
diff --git a/vector.rkt b/vector.rkt
index 3649de3..fdc3c38 100644
--- a/vector.rkt
+++ b/vector.rkt
@@ -67,7 +67,7 @@
    [(_ e* ...)
     #'(let e* ...)]))
 
-(define-for-syntax (vector-ref-error v i reason)
+(define-for-syntax (vector-ref-error v i)
   (raise-argument-error
     errloc-key
     (format "Index out-of-bounds: ~a" i)