diff --git a/internal/config/config_test.go b/internal/config/config_test.go
index c68b316..11875de 100644
--- a/internal/config/config_test.go
+++ b/internal/config/config_test.go
@@ -12,6 +12,8 @@ import (
 )
 
 func TestLegalServiceName(t *testing.T) {
+	t.Parallel()
+
 	tests := []struct {
 		Raw   string
 		Error error
@@ -51,7 +53,7 @@ func TestLegalServiceName(t *testing.T) {
 		},
 		{
 			`[ { "method": "GET", "info": "a", "path": "/invalid/{braces}" } ]`,
-			nil,
+			ErrUndefinedBraceCapture,
 		},
 		{
 			`[ { "method": "GET", "info": "a", "path": "/invalid/s{braces}/abc" } ]`,
@@ -63,7 +65,7 @@ func TestLegalServiceName(t *testing.T) {
 		},
 		{
 			`[ { "method": "GET", "info": "a", "path": "/invalid/{braces}/abc" } ]`,
-			nil,
+			ErrUndefinedBraceCapture,
 		},
 		{
 			`[ { "method": "GET", "info": "a", "path": "/invalid/{b{races}s/abc" } ]`,
@@ -99,6 +101,7 @@ func TestLegalServiceName(t *testing.T) {
 	}
 }
 func TestAvailableMethods(t *testing.T) {
+	t.Parallel()
 	tests := []struct {
 		Raw         string
 		ValidMethod bool
@@ -146,6 +149,7 @@ func TestAvailableMethods(t *testing.T) {
 	}
 }
 func TestParseEmpty(t *testing.T) {
+	t.Parallel()
 	reader := strings.NewReader(`[]`)
 	_, err := Parse(reader)
 	if err != nil {
@@ -167,6 +171,7 @@ func TestParseJsonError(t *testing.T) {
 }
 
 func TestParseMissingMethodDescription(t *testing.T) {
+	t.Parallel()
 	tests := []struct {
 		Raw              string
 		ValidDescription bool
@@ -217,6 +222,7 @@ func TestParseMissingMethodDescription(t *testing.T) {
 }
 
 func TestParamEmptyRenameNoRename(t *testing.T) {
+	t.Parallel()
 	reader := strings.NewReader(`[
 		{
 			"method": "GET",
@@ -247,6 +253,7 @@ func TestParamEmptyRenameNoRename(t *testing.T) {
 
 }
 func TestOptionalParam(t *testing.T) {
+	t.Parallel()
 	reader := strings.NewReader(`[
 		{
 			"method": "GET",
@@ -288,6 +295,7 @@ func TestOptionalParam(t *testing.T) {
 
 }
 func TestParseParameters(t *testing.T) {
+	t.Parallel()
 	tests := []struct {
 		Raw   string
 		Error error
@@ -473,6 +481,57 @@ func TestParseParameters(t *testing.T) {
 			]`,
 			nil,
 		},
+
+		{ // URI parameter
+			`[
+				{
+					"method": "GET",
+					"path": "/{uri}",
+					"info": "info",
+					"in": {
+						"{uri}": { "info": "valid", "type": "any", "name": "freename" }
+					}
+				}
+			]`,
+			nil,
+		},
+		{ // URI parameter cannot be optional
+			`[
+				{
+					"method": "GET",
+					"path": "/{uri}",
+					"info": "info",
+					"in": {
+						"{uri}": { "info": "valid", "type": "?any", "name": "freename" }
+					}
+				}
+			]`,
+			ErrIllegalOptionalURIParam,
+		},
+		{ // URI parameter not specified
+			`[
+				{
+					"method": "GET",
+					"path": "/",
+					"info": "info",
+					"in": {
+						"{uri}": { "info": "valid", "type": "?any", "name": "freename" }
+					}
+				}
+			]`,
+			ErrUnspecifiedBraceCapture,
+		},
+		{ // URI parameter not defined
+			`[
+				{
+					"method": "GET",
+					"path": "/{uri}",
+					"info": "info",
+					"in": { }
+				}
+			]`,
+			ErrUndefinedBraceCapture,
+		},
 	}
 
 	for i, test := range tests {
@@ -501,6 +560,7 @@ func TestParseParameters(t *testing.T) {
 }
 
 func TestMatchSimple(t *testing.T) {
+	t.Parallel()
 	tests := []struct {
 		Config string
 		URL    string
diff --git a/internal/config/errors.go b/internal/config/errors.go
index 7a5b9cc..994ddc1 100644
--- a/internal/config/errors.go
+++ b/internal/config/errors.go
@@ -29,9 +29,15 @@ const ErrInvalidPatternBraceCapture = Error("invalid uri capturing braces")
 // ErrUnspecifiedBraceCapture - a parameter brace capture is not specified in the pattern
 const ErrUnspecifiedBraceCapture = Error("capturing brace missing in the path")
 
+// ErrUndefinedBraceCapture - a parameter brace capture in the pattern is not defined in parameters
+const ErrUndefinedBraceCapture = Error("capturing brace missing input definition")
+
 // ErrMissingDescription - a service is missing its description
 const ErrMissingDescription = Error("missing description")
 
+// ErrIllegalOptionalURIParam - an URI parameter cannot be optional
+const ErrIllegalOptionalURIParam = Error("URI parameter cannot be optional")
+
 // ErrMissingParamDesc - a parameter is missing its description
 const ErrMissingParamDesc = Error("missing parameter description")
 
diff --git a/internal/config/server.go b/internal/config/server.go
index b197ee0..6347fdb 100644
--- a/internal/config/server.go
+++ b/internal/config/server.go
@@ -40,6 +40,17 @@ func Parse(r io.Reader, dtypes ...datatype.T) (*Server, error) {
 	return server, nil
 }
 
+// Find a service matching an incoming HTTP request
+func (server Server) Find(r *http.Request) *Service {
+	for _, service := range server.Services {
+		if matches := service.Match(r); matches {
+			return service
+		}
+	}
+
+	return nil
+}
+
 // collide returns if there is collision between services
 func (server *Server) collide() error {
 	length := len(server.Services)
@@ -120,17 +131,6 @@ func (server *Server) collide() error {
 	return nil
 }
 
-// Find a service matching an incoming HTTP request
-func (server Server) Find(r *http.Request) *Service {
-	for _, service := range server.Services {
-		if matches := service.Match(r); matches {
-			return service
-		}
-	}
-
-	return nil
-}
-
 // checkAndFormat checks for errors and missing fields and sets default values for optional fields.
 func (server Server) checkAndFormat() error {
 	for _, service := range server.Services {
@@ -159,6 +159,13 @@ func (server Server) checkAndFormat() error {
 			return fmt.Errorf("%s '%s' [in]: %w", service.Method, service.Pattern, err)
 		}
 
+		// fail if a brace capture remains undefined
+		for _, capture := range service.Captures {
+			if capture.Ref == nil {
+				return fmt.Errorf("%s '%s' [in]: %s: %w", service.Method, service.Pattern, capture.Name, ErrUndefinedBraceCapture)
+			}
+		}
+
 	}
 	return nil
 }
diff --git a/internal/config/service.go b/internal/config/service.go
index 90d6a1f..abe5e06 100644
--- a/internal/config/service.go
+++ b/internal/config/service.go
@@ -100,7 +100,8 @@ func (svc *Service) checkAndFormatInput(types []datatype.T) error {
 			return fmt.Errorf("%s: %w", paramName, ErrIllegalParamName)
 		}
 
-		// fail if brace does not exists in pattern
+		// fail if brace capture does not exists in pattern
+		iscapture := false
 		if matches := braceRegex.FindAllStringSubmatch(paramName, -1); len(matches) > 0 && len(matches[0]) > 1 {
 			braceName := matches[0][1]
 
@@ -115,6 +116,7 @@ func (svc *Service) checkAndFormatInput(types []datatype.T) error {
 			if !found {
 				return fmt.Errorf("%s: %w", paramName, ErrUnspecifiedBraceCapture)
 			}
+			iscapture = true
 		}
 
 		// use param name if no rename
@@ -127,6 +129,11 @@ func (svc *Service) checkAndFormatInput(types []datatype.T) error {
 			return fmt.Errorf("%s: %w", paramName, err)
 		}
 
+		// capture parameter cannot be optional
+		if iscapture && param.Optional {
+			return fmt.Errorf("%s: %w", paramName, ErrIllegalOptionalURIParam)
+		}
+
 		if !param.assignDataType(types) {
 			return fmt.Errorf("%s: %w", paramName, ErrUnknownDataType)
 		}