diff --git a/go.mod b/go.mod
index 5285ea20..f6f755cc 100644
--- a/go.mod
+++ b/go.mod
@@ -11,7 +11,7 @@ require (
 
 require (
 	github.com/itchyny/gojq v0.12.19
-	github.com/santhosh-tekuri/jsonschema/v6 v6.0.2
+	github.com/santhosh-tekuri/jsonschema/v6 v6.0.3
 	github.com/stretchr/testify v1.11.1
 	github.com/tetratelabs/wazero v1.12.0
 	go.opentelemetry.io/otel v1.44.0
diff --git a/go.sum b/go.sum
index f6c954e3..4b532ff7 100644
--- a/go.sum
+++ b/go.sum
@@ -43,8 +43,8 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
 github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
-github.com/santhosh-tekuri/jsonschema/v6 v6.0.2 h1:KRzFb2m7YtdldCEkzs6KqmJw4nqEVZGK7IN2kJkjTuQ=
-github.com/santhosh-tekuri/jsonschema/v6 v6.0.2/go.mod h1:JXeL+ps8p7/KNMjDQk3TCwPpBy0wYklyWTfbkIzdIFU=
+github.com/santhosh-tekuri/jsonschema/v6 v6.0.3 h1:1EYB5IzjZawrrnELUi78f9fPu57HuXjmddZPjrls/28=
+github.com/santhosh-tekuri/jsonschema/v6 v6.0.3/go.mod h1:JXeL+ps8p7/KNMjDQk3TCwPpBy0wYklyWTfbkIzdIFU=
 github.com/segmentio/asm v1.1.3 h1:WM03sfUOENvvKexOLp+pCqgb/WDjsi7EK8gIsICtzhc=
 github.com/segmentio/asm v1.1.3/go.mod h1:Ld3L4ZXGNcSLRg4JBsZ3//1+f/TjYl0Mzen/DQy1EJg=
 github.com/segmentio/encoding v0.5.4 h1:OW1VRern8Nw6ITAtwSZ7Idrl3MXCFwXHPgqESYfvNt0=
diff --git a/internal/config/validation_schema_test.go b/internal/config/validation_schema_test.go
index 66be316a..1fdb6ece 100644
--- a/internal/config/validation_schema_test.go
+++ b/internal/config/validation_schema_test.go
@@ -890,3 +890,27 @@ func TestSchema_OpenTelemetryConfig(t *testing.T) {
 		})
 	}
 }
+
+// TestValidateJSONSchema_CustomSchemasPropertyNamesLocation verifies that invalid
+// customSchemas key names are reported with the propertyNames instance path.
+func TestValidateJSONSchema_CustomSchemasPropertyNamesLocation(t *testing.T) {
+	config := `{
+		"mcpServers": {
+			"github": {
+				"container": "ghcr.io/github/github-mcp-server:latest"
+			}
+		},
+		"gateway": {
+			"port": 8080,
+			"domain": "localhost",
+			"agentId": "test-key"
+		},
+		"customSchemas": {
+			"Bad_Name": "https://example.com/schema.json"
+		}
+	}`
+
+	err := validateJSONSchema([]byte(config))
+	require.Error(t, err)
+	assert.ErrorContains(t, err, "Location: /customSchemas\n  Error: invalid propertyName 'Bad_Name'")
+}