diff --git a/internal/cerr/cerr.go b/internal/cerr/cerr.go
index 57f4431..19a8e6d 100644
--- a/internal/cerr/cerr.go
+++ b/internal/cerr/cerr.go
@@ -16,6 +16,14 @@ func (err Error) Wrap(e error) *WrapError {
 	}
 }
 
+// WrapString returns a new error which wraps a new error created from a string.
+func (err Error) WrapString(e string) *WrapError {
+	return &WrapError{
+		base: err,
+		wrap: Error(e),
+	}
+}
+
 // WrapError is way to wrap errors recursively.
 type WrapError struct {
 	base error
diff --git a/internal/cerr/cerr_test.go b/internal/cerr/cerr_test.go
new file mode 100644
index 0000000..476996c
--- /dev/null
+++ b/internal/cerr/cerr_test.go
@@ -0,0 +1,57 @@
+package cerr
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+)
+
+func TestConstError(t *testing.T) {
+	const cerr1 = Error("some-string")
+	const cerr2 = Error("some-other-string")
+	const cerr3 = Error("some-string") // same const value as @cerr1
+
+	if cerr1.Error() == cerr2.Error() {
+		t.Errorf("cerr1 should not be equal to cerr2 ('%s', '%s')", cerr1.Error(), cerr2.Error())
+	}
+	if cerr2.Error() == cerr3.Error() {
+		t.Errorf("cerr2 should not be equal to cerr3 ('%s', '%s')", cerr2.Error(), cerr3.Error())
+	}
+	if cerr1.Error() != cerr3.Error() {
+		t.Errorf("cerr1 should be equal to cerr3 ('%s', '%s')", cerr1.Error(), cerr3.Error())
+	}
+}
+
+func TestWrappedConstError(t *testing.T) {
+	const parent = Error("file error")
+
+	const readErrorConst = Error("cannot read file")
+	var wrappedReadError = parent.Wrap(readErrorConst)
+
+	expectedWrappedReadError := fmt.Sprintf("%s: %s", parent.Error(), readErrorConst.Error())
+	if wrappedReadError.Error() != expectedWrappedReadError {
+		t.Errorf("expected '%s' (got '%s')", wrappedReadError.Error(), expectedWrappedReadError)
+	}
+}
+func TestWrappedStandardError(t *testing.T) {
+	const parent = Error("file error")
+
+	var writeErrorStandard error = errors.New("cannot write file")
+	var wrappedWriteError = parent.Wrap(writeErrorStandard)
+
+	expectedWrappedWriteError := fmt.Sprintf("%s: %s", parent.Error(), writeErrorStandard.Error())
+	if wrappedWriteError.Error() != expectedWrappedWriteError {
+		t.Errorf("expected '%s' (got '%s')", wrappedWriteError.Error(), expectedWrappedWriteError)
+	}
+}
+func TestWrappedStringError(t *testing.T) {
+	const parent = Error("file error")
+
+	var closeErrorString string = "cannot close file"
+	var wrappedCloseError = parent.WrapString(closeErrorString)
+
+	expectedWrappedCloseError := fmt.Sprintf("%s: %s", parent.Error(), closeErrorString)
+	if wrappedCloseError.Error() != expectedWrappedCloseError {
+		t.Errorf("expected '%s' (got '%s')", wrappedCloseError.Error(), expectedWrappedCloseError)
+	}
+}
diff --git a/internal/config/config_test.go b/internal/config/config_test.go
new file mode 100644
index 0000000..deb3170
--- /dev/null
+++ b/internal/config/config_test.go
@@ -0,0 +1,636 @@
+package config
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestLegalServiceName(t *testing.T) {
+	tests := []struct {
+		Raw   string
+		Error error
+	}{
+		{
+			`{
+				"/": {
+					"invalid/service-name": {
+
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrIllegalServiceName.WrapString("invalid/service-name")),
+		},
+		{
+			`{
+				"/": {
+					"invalid/service/name": {
+
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrIllegalServiceName.WrapString("invalid/service/name")),
+		},
+		{
+			`{
+				"/": {
+					"invalid-service-name": {
+
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrIllegalServiceName.WrapString("invalid-service-name")),
+		},
+
+		{
+			`{
+				"/": {
+					"valid.service_name": {
+					}
+				}
+			}`,
+			nil,
+		},
+	}
+
+	for i, test := range tests {
+
+		t.Run(fmt.Sprintf("service.%d", i), func(t *testing.T) {
+			_, err := Parse(strings.NewReader(test.Raw))
+
+			if err == nil && test.Error != nil {
+				t.Errorf("expected an error: '%s'", test.Error.Error())
+				t.FailNow()
+			}
+			if err != nil && test.Error == nil {
+				t.Errorf("unexpected error: '%s'", err.Error())
+				t.FailNow()
+			}
+
+			if err != nil && test.Error != nil {
+				if err.Error() != test.Error.Error() {
+					t.Errorf("expected the error '%s' (got '%s')", test.Error.Error(), err.Error())
+					t.FailNow()
+				}
+			}
+		})
+	}
+}
+func TestAvailableMethods(t *testing.T) {
+	reader := strings.NewReader(`{
+		"GET": { "info": "info" },
+		"POST": { "info": "info" },
+		"PUT": { "info": "info" },
+		"DELETE": { "info": "info" }
+	}`)
+	srv, err := Parse(reader)
+	if err != nil {
+		t.Errorf("unexpected error (got '%s')", err)
+		t.FailNow()
+	}
+
+	if srv.Method(http.MethodGet) == nil {
+		t.Errorf("expected method GET to be available")
+		t.Fail()
+	}
+	if srv.Method(http.MethodPost) == nil {
+		t.Errorf("expected method POST to be available")
+		t.Fail()
+	}
+	if srv.Method(http.MethodPut) == nil {
+		t.Errorf("expected method PUT to be available")
+		t.Fail()
+	}
+	if srv.Method(http.MethodDelete) == nil {
+		t.Errorf("expected method DELETE to be available")
+		t.Fail()
+	}
+
+	if srv.Method(http.MethodPatch) != nil {
+		t.Errorf("expected method PATH to be UNavailable")
+		t.Fail()
+	}
+}
+func TestParseEmpty(t *testing.T) {
+	reader := strings.NewReader(`{}`)
+	_, err := Parse(reader)
+	if err != nil {
+		t.Errorf("unexpected error (got '%s')", err)
+		t.FailNow()
+	}
+}
+func TestParseJsonError(t *testing.T) {
+	reader := strings.NewReader(`{
+		"GET": {
+			"info": "info
+		},
+	}`) // trailing ',' is invalid JSON
+	_, err := Parse(reader)
+	if err == nil {
+		t.Errorf("expected error")
+		t.FailNow()
+	}
+}
+
+func TestParseMissingMethodDescription(t *testing.T) {
+	tests := []struct {
+		Raw   string
+		Error error
+	}{
+		{ // missing description
+			`{
+				"GET": {
+
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingMethodDesc.WrapString("GET /")),
+		},
+		{ // missing description
+			`{
+				"/": {
+					"subservice": {
+						"GET": {
+
+						}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingMethodDesc.WrapString("GET subservice")),
+		},
+		{ // empty description
+			`{
+				"GET": {
+					"info": ""
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingMethodDesc.WrapString("GET /")),
+		},
+		{ // valid description
+			`{
+				"GET": {
+					"info": "a"
+				}
+			}`,
+			nil,
+		},
+		{ // valid description
+			`{
+				"GET": {
+					"info": "some description"
+				}
+			}`,
+			nil,
+		},
+	}
+
+	for i, test := range tests {
+
+		t.Run(fmt.Sprintf("method.%d", i), func(t *testing.T) {
+			_, err := Parse(strings.NewReader(test.Raw))
+
+			if err == nil && test.Error != nil {
+				t.Errorf("expected an error: '%s'", test.Error.Error())
+				t.FailNow()
+			}
+			if err != nil && test.Error == nil {
+				t.Errorf("unexpected error: '%s'", err.Error())
+				t.FailNow()
+			}
+
+			if err != nil && test.Error != nil {
+				if err.Error() != test.Error.Error() {
+					t.Errorf("expected the error '%s' (got '%s')", test.Error.Error(), err.Error())
+					t.FailNow()
+				}
+			}
+		})
+	}
+
+}
+
+func TestParamEmptyRenameNoRename(t *testing.T) {
+	reader := strings.NewReader(`{
+		"GET": {
+			"info": "info",
+			"in": {
+				"original": { "info": "valid-desc", "type": "valid-type", "name": "" }
+			}
+		}
+	}`)
+	srv, err := Parse(reader)
+	if err != nil {
+		t.Errorf("unexpected error: '%s'", err)
+		t.FailNow()
+	}
+
+	method := srv.Method(http.MethodGet)
+	if method == nil {
+		t.Errorf("expected GET method not to be nil")
+		t.FailNow()
+	}
+	for _, param := range method.Parameters {
+
+		if param.Rename != "original" {
+			t.Errorf("expected the parameter 'original' not to be renamed to '%s'", param.Rename)
+			t.FailNow()
+		}
+	}
+
+}
+func TestOptionalParam(t *testing.T) {
+	reader := strings.NewReader(`{
+		"GET": {
+			"info": "info",
+			"in": {
+				"optional": { "info": "valid-desc", "type": "?optional-type" },
+				"required": { "info": "valid-desc", "type": "required-type" },
+				"required2": { "info": "valid-desc", "type": "a" },
+				"optional2": { "info": "valid-desc", "type": "?a" }
+			}
+		}
+	}`)
+	srv, err := Parse(reader)
+	if err != nil {
+		t.Errorf("unexpected error: '%s'", err)
+		t.FailNow()
+	}
+
+	method := srv.Method(http.MethodGet)
+	if method == nil {
+		t.Errorf("expected GET method not to be nil")
+		t.FailNow()
+	}
+	for pName, param := range method.Parameters {
+
+		if pName == "optional" || pName == "optional2" {
+			if !param.Optional {
+				t.Errorf("expected parameter '%s' to be optional", pName)
+				t.Failed()
+			}
+		}
+		if pName == "required" || pName == "required2" {
+			if param.Optional {
+				t.Errorf("expected parameter '%s' to be required", pName)
+				t.Failed()
+			}
+		}
+	}
+
+}
+func TestParseParameters(t *testing.T) {
+	tests := []struct {
+		Raw              string
+		Error            error
+		ErrorAlternative error
+	}{
+		{ // invalid param name prefix
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"_param1": {}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrIllegalParamName.WrapString("GET / {_param1}")),
+			nil,
+		},
+		{ // invalid param name suffix
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1_": {}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrIllegalParamName.WrapString("GET / {param1_}")),
+			nil,
+		},
+
+		{ // missing param description
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingParamDesc.WrapString("GET / {param1}")),
+			nil,
+		},
+		{ // empty param description
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {
+							"info": ""
+						}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingParamDesc.WrapString("GET / {param1}")),
+			nil,
+		},
+
+		{ // missing param type
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {
+							"info": "valid"
+						}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingParamType.WrapString("GET / {param1}")),
+			nil,
+		},
+		{ // empty param type
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {
+							"info": "valid",
+							"type": ""
+						}
+					}
+				}
+			}`,
+			ErrFormat.Wrap(ErrMissingParamType.WrapString("GET / {param1}")),
+			nil,
+		},
+		{ // invalid type (optional mark only)
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {
+							"info": "valid",
+							"type": "?"
+						}
+					}
+				}
+			}`,
+
+			ErrFormat.Wrap(ErrMissingParamType.WrapString("GET / {param1}")),
+			ErrFormat.Wrap(ErrMissingParamType.WrapString("GET / {param1}")),
+		},
+		{ // valid description + valid type
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {
+							"info": "valid",
+							"type": "a"
+						}
+					}
+				}
+			}`,
+			nil,
+			nil,
+		},
+		{ // valid description + valid OPTIONAL type
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": {
+							"info": "valid",
+							"type": "?valid"
+						}
+					}
+				}
+			}`,
+			nil,
+			nil,
+		},
+
+		{ // name conflict with rename
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": { "info": "valid", "type": "valid" },
+						"param2": { "info": "valid", "type": "valid", "name": "param1" }
+
+					}
+				}
+			}`,
+			// 2 possible errors as map order is not deterministic
+			ErrFormat.Wrap(ErrParamNameConflict.WrapString("GET / {param1}")),
+			ErrFormat.Wrap(ErrParamNameConflict.WrapString("GET / {param2}")),
+		},
+		{ // rename conflict with name
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": { "info": "valid", "type": "valid", "name": "param2" },
+						"param2": { "info": "valid", "type": "valid" }
+
+					}
+				}
+			}`,
+			// 2 possible errors as map order is not deterministic
+			ErrFormat.Wrap(ErrParamNameConflict.WrapString("GET / {param1}")),
+			ErrFormat.Wrap(ErrParamNameConflict.WrapString("GET / {param2}")),
+		},
+		{ // rename conflict with rename
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": { "info": "valid", "type": "valid", "name": "conflict" },
+						"param2": { "info": "valid", "type": "valid", "name": "conflict" }
+
+					}
+				}
+			}`,
+			// 2 possible errors as map order is not deterministic
+			ErrFormat.Wrap(ErrParamNameConflict.WrapString("GET / {param1}")),
+			ErrFormat.Wrap(ErrParamNameConflict.WrapString("GET / {param2}")),
+		},
+
+		{ // both renamed with no conflict
+			`{
+				"GET": {
+					"info": "info",
+					"in": {
+						"param1": { "info": "valid", "type": "valid", "name": "freename" },
+						"param2": { "info": "valid", "type": "valid", "name": "freename2" }
+
+					}
+				}
+			}`,
+			nil,
+			nil,
+		},
+	}
+
+	for i, test := range tests {
+
+		t.Run(fmt.Sprintf("method.%d", i), func(t *testing.T) {
+			_, err := Parse(strings.NewReader(test.Raw))
+
+			if err == nil && test.Error != nil {
+				t.Errorf("expected an error: '%s'", test.Error.Error())
+				t.FailNow()
+			}
+			if err != nil && test.Error == nil {
+				t.Errorf("unexpected error: '%s'", err.Error())
+				t.FailNow()
+			}
+
+			if err != nil && test.Error != nil {
+				if err.Error() != test.Error.Error() && err.Error() != test.ErrorAlternative.Error() {
+					t.Errorf("got the error: '%s'", err.Error())
+					t.Errorf("expected error (alternative 1): '%s'", test.Error.Error())
+					t.Errorf("expected error (alternative 2): '%s'", test.ErrorAlternative.Error())
+					t.FailNow()
+				}
+			}
+		})
+	}
+
+}
+
+func TestBrowseSimple(t *testing.T) {
+	tests := []struct {
+		Raw         string
+		Path        []string
+		BrowseDepth int
+		ValidDepth  bool
+	}{
+		{ // false positive -1
+			`{
+				"/" : {
+					"parent": {
+						"/": {
+							"subdir": {}
+						}
+					}
+				}
+			}`,
+			[]string{"parent", "subdir"},
+			1,
+			false,
+		},
+		{ // false positive +1
+			`{
+				"/" : {
+					"parent": {
+						"/": {
+							"subdir": {}
+						}
+					}
+				}
+			}`,
+			[]string{"parent", "subdir"},
+			3,
+			false,
+		},
+
+		{
+			`{
+				"/" : {
+					"parent": {
+						"/": {
+							"subdir": {}
+						}
+					}
+				}
+			}`,
+			[]string{"parent", "subdir"},
+			2,
+			true,
+		},
+		{ // unknown path
+			`{
+				"/" : {
+					"parent": {
+						"/": {
+							"subdir": {}
+						}
+					}
+				}
+			}`,
+			[]string{"x", "y"},
+			2,
+			false,
+		},
+		{ // unknown path
+			`{
+				"/" : {
+					"parent": {
+						"/": {
+							"subdir": {}
+						}
+					}
+				}
+			}`,
+			[]string{"parent", "y"},
+			1,
+			true,
+		},
+		{ // Warning: this case is important to understand the precedence of service paths over
+			// the value of some variables. Here if we send a string parameter in the GET method that
+			// unfortunately is equal to 'subdir', it will call the sub-service /parent/subdir' instead
+			// of the service /parent with its parameter set to the value 'subdir'.
+			`{
+				"/" : {
+					"parent": {
+						"/": {
+							"subdir": {}
+						},
+						"GET": {
+							"info": "valid-desc",
+							"in": {
+								"some-value": {
+									"info": "valid-desc",
+									"type": "valid-type"
+								}
+							}
+						}
+					}
+				}
+			}`,
+			[]string{"parent", "subdir"},
+			2,
+			true,
+		},
+	}
+
+	for i, test := range tests {
+
+		t.Run(fmt.Sprintf("method.%d", i), func(t *testing.T) {
+			srv, err := Parse(strings.NewReader(test.Raw))
+
+			if err != nil {
+				t.Errorf("unexpected error: '%s'", err)
+				t.FailNow()
+			}
+
+			_, depth := srv.Browse(test.Path)
+			if test.ValidDepth {
+				if depth != test.BrowseDepth {
+					t.Errorf("expected a depth of %d (got %d)", test.BrowseDepth, depth)
+					t.FailNow()
+				}
+			} else {
+				if depth == test.BrowseDepth {
+					t.Errorf("expected a depth NOT %d (got %d)", test.BrowseDepth, depth)
+					t.FailNow()
+				}
+
+			}
+		})
+	}
+
+}
diff --git a/internal/config/errors.go b/internal/config/errors.go
new file mode 100644
index 0000000..ef413e8
--- /dev/null
+++ b/internal/config/errors.go
@@ -0,0 +1,27 @@
+package config
+
+import "git.xdrm.io/go/aicra/internal/cerr"
+
+// ErrRead - a problem ocurred when trying to read the configuration file
+const ErrRead = cerr.Error("cannot read config")
+
+// ErrFormat - a invalid format has been detected
+const ErrFormat = cerr.Error("invalid config format")
+
+// ErrIllegalServiceName - an illegal character has been found in a service name
+const ErrIllegalServiceName = cerr.Error("service must not contain any slash '/' nor '-' symbols")
+
+// ErrMissingMethodDesc - a method is missing its description
+const ErrMissingMethodDesc = cerr.Error("missing method description")
+
+// ErrMissingParamDesc - a parameter is missing its description
+const ErrMissingParamDesc = cerr.Error("missing parameter description")
+
+// ErrIllegalParamName - a parameter has an illegal name
+const ErrIllegalParamName = cerr.Error("illegal parameter name (must not begin/end with '_')")
+
+// ErrMissingParamType - a parameter has an illegal type
+const ErrMissingParamType = cerr.Error("missing parameter type")
+
+// ErrParamNameConflict - a parameter has a conflict with its name/rename field
+const ErrParamNameConflict = cerr.Error("name conflict for parameter")
diff --git a/internal/config/method.go b/internal/config/method.go
index f570b84..14c3539 100644
--- a/internal/config/method.go
+++ b/internal/config/method.go
@@ -1,7 +1,6 @@
 package config
 
 import (
-	"fmt"
 	"strings"
 )
 
@@ -10,7 +9,7 @@ func (methodDef *Method) checkAndFormat(servicePath string, httpMethod string) e
 
 	// 1. fail on missing description
 	if len(methodDef.Description) < 1 {
-		return fmt.Errorf("missing %s.%s description", servicePath, httpMethod)
+		return ErrMissingMethodDesc.WrapString(httpMethod + " " + servicePath)
 	}
 
 	// 2. stop if no parameter
@@ -22,16 +21,16 @@ func (methodDef *Method) checkAndFormat(servicePath string, httpMethod string) e
 	// 3. for each parameter
 	for pName, pData := range methodDef.Parameters {
 
-		// check name
+		// 3.1. check name
 		if strings.Trim(pName, "_") != pName {
-			return fmt.Errorf("invalid name '%s' must not begin/end with '_'", pName)
+			return ErrIllegalParamName.WrapString(httpMethod + " " + servicePath + " {" + pName + "}")
 		}
 
 		if len(pData.Rename) < 1 {
 			pData.Rename = pName
 		}
 
-		// 5. Check for name/rename conflict
+		// 3.2. Check for name/rename conflict
 		for paramName, param := range methodDef.Parameters {
 
 			// ignore self
@@ -39,39 +38,26 @@ func (methodDef *Method) checkAndFormat(servicePath string, httpMethod string) e
 				continue
 			}
 
-			// 1. Same rename field
-			if pData.Rename == param.Rename {
-				return fmt.Errorf("rename conflict for %s.%s parameter '%s'", servicePath, httpMethod, pData.Rename)
-			}
-
-			// 2. Not-renamed field matches a renamed field
-			if pName == param.Rename {
-				return fmt.Errorf("name conflict for %s.%s parameter '%s'", servicePath, httpMethod, pName)
-			}
-
-			// 3. Renamed field matches name
-			if pData.Rename == paramName {
-				return fmt.Errorf("name conflict for %s.%s parameter '%s'", servicePath, httpMethod, pName)
+			// 3.2.1. Same rename field
+			// 3.2.2. Not-renamed field matches a renamed field
+			// 3.2.3. Renamed field matches name
+			if pData.Rename == param.Rename || pName == param.Rename || pData.Rename == paramName {
+				return ErrParamNameConflict.WrapString(httpMethod + " " + servicePath + " {" + pName + "}")
 			}
 
 		}
 
-		// 6. Manage invalid type
-		if len(pData.Type) < 1 {
-			return fmt.Errorf("invalid type for %s.%s parameter '%s'", servicePath, httpMethod, pName)
-		}
-
-		// 7. Fail on missing description
+		// 3.3. Fail on missing description
 		if len(pData.Description) < 1 {
-			return fmt.Errorf("missing description for %s.%s parameter '%s'", servicePath, httpMethod, pName)
+			return ErrMissingParamDesc.WrapString(httpMethod + " " + servicePath + " {" + pName + "}")
 		}
 
-		// 8. Fail on missing type
-		if len(pData.Type) < 1 {
-			return fmt.Errorf("missing type for %s.%s parameter '%s'", servicePath, httpMethod, pName)
+		// 3.4. Manage invalid type
+		if len(pData.Type) < 1 || pData.Type == "?" {
+			return ErrMissingParamType.WrapString(httpMethod + " " + servicePath + " {" + pName + "}")
 		}
 
-		// 9. Set optional + type
+		// 3.5. Set optional + type
 		if pData.Type[0] == '?' {
 			pData.Optional = true
 			pData.Type = pData.Type[1:]
@@ -81,13 +67,3 @@ func (methodDef *Method) checkAndFormat(servicePath string, httpMethod string) e
 
 	return nil
 }
-
-// scopeHasPermission returns whether the permission fulfills a given scope
-func scopeHasPermission(permission string, scope []string) bool {
-	for _, s := range scope {
-		if permission == s {
-			return true
-		}
-	}
-	return false
-}
diff --git a/internal/config/service.go b/internal/config/service.go
index cf223fe..1c97701 100644
--- a/internal/config/service.go
+++ b/internal/config/service.go
@@ -2,20 +2,11 @@ package config
 
 import (
 	"encoding/json"
-	"fmt"
 	"io"
 	"net/http"
 	"strings"
-
-	"git.xdrm.io/go/aicra/internal/cerr"
 )
 
-// ErrRead - a problem ocurred when trying to read the configuration file
-const ErrRead = cerr.Error("cannot read config")
-
-// ErrFormat - a invalid format has been detected
-const ErrFormat = cerr.Error("invalid config format")
-
 // Parse builds a service from a json reader and checks for most format errors.
 func Parse(r io.Reader) (*Service, error) {
 	receiver := &Service{}
@@ -87,20 +78,20 @@ func (svc *Service) checkAndFormat(servicePath string) error {
 		}
 	}
 
-	// 1. stop if no child */
+	// 2. stop if no child */
 	if svc.Children == nil || len(svc.Children) < 1 {
 		return nil
 	}
 
-	// 2. for each service */
+	// 3. for each service */
 	for childService, ctl := range svc.Children {
 
-		// 3. invalid name */
+		// 3.1. invalid name */
 		if strings.ContainsAny(childService, "/-") {
-			return fmt.Errorf("service '%s' must not contain any slash '/' nor '-' symbols", childService)
+			return ErrIllegalServiceName.WrapString(childService)
 		}
 
-		// 4. check recursively */
+		// 3.2. check recursively */
 		err := ctl.checkAndFormat(childService)
 		if err != nil {
 			return err