diff --git a/pkg/yqlib/doc/Document Index.md b/pkg/yqlib/doc/Document Index.md
index 024e4916..f9a2366e 100644
--- a/pkg/yqlib/doc/Document Index.md	
+++ b/pkg/yqlib/doc/Document Index.md	
@@ -1,4 +1,4 @@
-Use the `documentIndex` operator to select nodes of a particular document.
+Use the `documentIndex` operator (or the `di` shorthand) to select nodes of a particular document.
 ## Retrieve a document index
 Given a sample.yml file of:
 ```yaml
diff --git a/pkg/yqlib/operator_env.go b/pkg/yqlib/operator_env.go
index 4cfeeb3c..f80a700c 100644
--- a/pkg/yqlib/operator_env.go
+++ b/pkg/yqlib/operator_env.go
@@ -2,6 +2,7 @@ package yqlib
 
 import (
 	"container/list"
+	"fmt"
 	"os"
 	"strings"
 
@@ -27,6 +28,8 @@ func EnvOperator(d *dataTreeNavigator, matchMap *list.List, pathNode *PathTreeNo
 			Tag:   "!!str",
 			Value: rawValue,
 		}
+	} else if rawValue == "" {
+		return nil, fmt.Errorf("Value for env variable '%v' not provided in env()", envName)
 	} else {
 		var dataBucket yaml.Node
 		decoder := yaml.NewDecoder(strings.NewReader(rawValue))
diff --git a/pkg/yqlib/operator_recursive_descent_test.go b/pkg/yqlib/operator_recursive_descent_test.go
index 5f63d329..6f5b2900 100644
--- a/pkg/yqlib/operator_recursive_descent_test.go
+++ b/pkg/yqlib/operator_recursive_descent_test.go
@@ -63,10 +63,10 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		},
 	},
 	{
-		description: "Recursively find nodes with keys",
+		description:    "Recursively find nodes with keys",
 		subdescription: "Note that this example has wrapped the expression in `[]` to show that there are two matches returned. You do not have to wrap in `[]` in your path expression.",
-		document:    `{a: {name: frog, b: {name: blog, age: 12}}}`,
-		expression:  `[.. | select(has("name"))]`,
+		document:       `{a: {name: frog, b: {name: blog, age: 12}}}`,
+		expression:     `[.. | select(has("name"))]`,
 		expected: []string{
 			"D0, P[a], (!!seq)::- {name: frog, b: {name: blog, age: 12}}\n- {name: blog, age: 12}\n",
 		},