Fix advanced search not enabled for fields

Author: kelsey-myers

pkg/github/issues_test.go

@@ -744,6 +744,47 @@ func Test_SearchIssues(t *testing.T) {
 			expectError:    false,
 			expectedResult: mockSearchResult,
 		},
+		{
+			name: "query with field. qualifier enables advanced_search",
+			mockedClient: MockHTTPClientWithHandlers(map[string]http.HandlerFunc{
+				GetSearchIssues: expectQueryParams(
+					t,
+					map[string]string{
+						"q":               "is:issue field.priority:P1",
+						"page":            "1",
+						"per_page":        "30",
+						"advanced_search": "true",
+					},
+				).andThen(
+					mockResponse(t, http.StatusOK, mockSearchResult),
+				),
+			}),
+			requestArgs: map[string]any{
+				"query": "field.priority:P1",
+			},
+			expectError:    false,
+			expectedResult: mockSearchResult,
+		},
+		{
+			name: "query without field. qualifier does not set advanced_search",
+			mockedClient: MockHTTPClientWithHandlers(map[string]http.HandlerFunc{
+				GetSearchIssues: expectQueryParams(
+					t,
+					map[string]string{
+						"q":        "is:issue is:open",
+						"page":     "1",
+						"per_page": "30",
+					},
+				).andThen(
+					mockResponse(t, http.StatusOK, mockSearchResult),
+				),
+			}),
+			requestArgs: map[string]any{
+				"query": "is:open",
+			},
+			expectError:    false,
+			expectedResult: mockSearchResult,
+		},
 		{
 			name: "search issues fails",
 			mockedClient: MockHTTPClientWithHandlers(map[string]http.HandlerFunc{

pkg/github/search_utils.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"net/http"
 	"regexp"
+	"strings"
 
 	ghErrors "github.com/github/github-mcp-server/pkg/errors"
 	"github.com/github/github-mcp-server/pkg/utils"
@@ -94,14 +95,21 @@ func prepareSearchArgs(args map[string]any, searchType string) (string, *github.
 		return "", nil, err
 	}
 
-	return query, &github.SearchOptions{
+	opts := &github.SearchOptions{
 		Sort:  sort,
 		Order: order,
 		ListOptions: github.ListOptions{
 			Page:    pagination.Page,
 			PerPage: pagination.PerPage,
 		},
-	}, nil
+	}
+
+	// field.<name>:<value> qualifiers require the advanced search API.
+	if strings.Contains(query, "field.") {
+		opts.AdvancedSearch = github.Ptr(true)
+	}
+
+	return query, opts, nil
 }
 
 func searchHandler(