diff --git a/go/tools/builders/compile.go b/go/tools/builders/compile.go
index 81c8afa9cf..59337d8321 100644
--- a/go/tools/builders/compile.go
+++ b/go/tools/builders/compile.go
@@ -17,6 +17,7 @@
 package main
 
 import (
+	"bytes"
 	"flag"
 	"fmt"
 	"go/build"
@@ -128,6 +129,8 @@ func run(args []string) error {
 }
 
 func main() {
+	log.SetFlags(0) // no timestamp
+	log.SetPrefix("GoCompile: ")
 	if err := run(os.Args[1:]); err != nil {
 		log.Fatal(err)
 	}
@@ -151,7 +154,7 @@ func checkDirectDeps(bctx build.Context, files []*goMetadata, deps []string, pac
 		depSet[d] = true
 	}
 
-	var errs depsError
+	derr := depsError{known: deps}
 	for _, f := range files {
 		for _, path := range f.imports {
 			if path == "C" || stdlib[path] || isRelative(path) {
@@ -161,26 +164,43 @@ func checkDirectDeps(bctx build.Context, files []*goMetadata, deps []string, pac
 				continue
 			}
 			if !depSet[path] {
-				errs = append(errs, fmt.Errorf("%s: import of %s, which is not a direct dependency", f.filename, path))
+				derr.missing = append(derr.missing, missingDep{f.filename, path})
 			}
 		}
 	}
-	if len(errs) > 0 {
-		return errs
+	if len(derr.missing) > 0 {
+		return derr
 	}
 	return nil
 }
 
-type depsError []error
+type depsError struct {
+	missing []missingDep
+	known   []string
+}
+
+type missingDep struct {
+	filename, imp string
+}
 
-var _ error = depsError(nil)
+var _ error = depsError{}
 
 func (e depsError) Error() string {
-	errorStrings := make([]string, len(e))
-	for i, err := range e {
-		errorStrings[i] = err.Error()
+	buf := bytes.NewBuffer(nil)
+	fmt.Fprintf(buf, "missing strict dependencies:\n")
+	for _, dep := range e.missing {
+		fmt.Fprintf(buf, "\t%s: import of %q\n", dep.filename, dep.imp)
+	}
+	if len(e.known) == 0 {
+		fmt.Fprintln(buf, "No dependencies were provided.")
+	} else {
+		fmt.Fprintln(buf, "Known dependencies are:")
+		for _, imp := range e.known {
+			fmt.Fprintf(buf, "\t%s\n", imp)
+		}
 	}
-	return "missing strict dependencies:\n\t" + strings.Join(errorStrings, "\n\t")
+	fmt.Fprint(buf, "Check that imports in Go sources match importpath attributes in deps.")
+	return buf.String()
 }
 
 func isRelative(path string) bool {