Fix handling nil values for optional string array parameters,

A-Georgiou · A-Georgiou · commit ec8398f47bf3 · 2025-04-09T13:20:10.000Z
nil values should be equivalent to an empty string, currently we return an error but Claude passes nil for optional values.
diff --git a/pkg/github/issues_test.go b/pkg/github/issues_test.go
@@ -471,6 +471,7 @@ func Test_CreateIssue(t *testing.T) {
 				"owner": "owner",
 				"repo":  "repo",
 				"title": "Minimal Issue",
+				"assignees": nil,	// Expect no failure with nil optional value.
 			},
 			expectError: false,
 			expectedIssue: &github.Issue{
diff --git a/pkg/github/server.go b/pkg/github/server.go
@@ -232,12 +232,14 @@ func OptionalIntParamWithDefault(r mcp.CallToolRequest, p string, d int) (int, e
 // 1. Checks if the parameter is present in the request, if not, it returns its zero-value
 // 2. If it is present, iterates the elements and checks each is a string
 func OptionalStringArrayParam(r mcp.CallToolRequest, p string) ([]string, error) {
-	// Check if the parameter is present in the request
+    // Check if the parameter is present in the request
 	if _, ok := r.Params.Arguments[p]; !ok {
 		return []string{}, nil
 	}
 
-	switch v := r.Params.Arguments[p].(type) {
+    switch v := r.Params.Arguments[p].(type) {
+	case nil:
+		return []string{}, nil
 	case []string:
 		return v, nil
 	case []any:
