github · tgockel · Aug 13, 2026
@@ -50,6 +50,7 @@
             "state",
             "user",
             "labels",
+            "assignees",
             "comments",
             "created_at",
             "updated_at",

@@ -274,7 +274,7 @@ func Test_SearchIssues_FieldsTelemetry(t *testing.T) {
 // getIssueQueryType; see Test_ListIssues for the canonical copies.
 const listIssuesFieldsFieldValuesSelection = "issueFieldValues(first: 25){nodes{__typename,... on IssueFieldDateValue{field{... on IssueFieldDate{name,fullDatabaseId},... on IssueFieldNumber{name,fullDatabaseId},... on IssueFieldSingleSelect{name,fullDatabaseId},... on IssueFieldText{name,fullDatabaseId}},value},... on IssueFieldNumberValue{field{... on IssueFieldDate{name,fullDatabaseId},... on IssueFieldNumber{name,fullDatabaseId},... on IssueFieldSingleSelect{name,fullDatabaseId},... on IssueFieldText{name,fullDatabaseId}},valueNumber: value},... on IssueFieldSingleSelectValue{field{... on IssueFieldDate{name,fullDatabaseId},... on IssueFieldNumber{name,fullDatabaseId},... on IssueFieldSingleSelect{name,fullDatabaseId},... on IssueFieldText{name,fullDatabaseId}},value},... on IssueFieldTextValue{field{... on IssueFieldDate{name,fullDatabaseId},... on IssueFieldNumber{name,fullDatabaseId},... on IssueFieldSingleSelect{name,fullDatabaseId},... on IssueFieldText{name,fullDatabaseId}},value}}}"
 
-const listIssuesFieldsQuery = "query($after:String$direction:OrderDirection!$first:Int!$issueFieldValues:[IssueFieldValueFilter!]!$orderBy:IssueOrderField!$owner:String!$repo:String!$states:[IssueState!]!){repository(owner: $owner, name: $repo){issues(first: $first, after: $after, states: $states, orderBy: {field: $orderBy, direction: $direction}, filterBy: {issueFieldValues: $issueFieldValues}){nodes{number,title,body,state,databaseId,author{login},createdAt,updatedAt,labels(first: 100){nodes{name,id,description}},comments{totalCount}," + listIssuesFieldsFieldValuesSelection + "},pageInfo{hasNextPage,hasPreviousPage,startCursor,endCursor},totalCount},isPrivate}}"
+const listIssuesFieldsQuery = "query($after:String$direction:OrderDirection!$first:Int!$issueFieldValues:[IssueFieldValueFilter!]!$orderBy:IssueOrderField!$owner:String!$repo:String!$states:[IssueState!]!){repository(owner: $owner, name: $repo){issues(first: $first, after: $after, states: $states, orderBy: {field: $orderBy, direction: $direction}, filterBy: {issueFieldValues: $issueFieldValues}){nodes{number,title,body,state,databaseId,author{login},createdAt,updatedAt,labels(first: 100){nodes{name,id,description}},assignees(first: 100){nodes{login}},comments{totalCount}," + listIssuesFieldsFieldValuesSelection + "},pageInfo{hasNextPage,hasPreviousPage,startCursor,endCursor},totalCount},isPrivate}}"
 
 func listIssuesFieldsMockClient() *http.Client {
 	vars := map[string]any{
@@ -301,6 +301,7 @@ func listIssuesFieldsMockClient() *http.Client {
 						"updatedAt":        "2023-01-01T00:00:00Z",
 						"author":           map[string]any{"login": "user1"},
 						"labels":           map[string]any{"nodes": []map[string]any{}},
+						"assignees":        map[string]any{"nodes": []map[string]any{{"login": "octocat"}}},
 						"comments":         map[string]any{"totalCount": 1},
 						"issueFieldValues": map[string]any{"nodes": []map[string]any{}},
 					},
@@ -353,6 +354,57 @@ func Test_ListIssues_FieldFiltering(t *testing.T) {
 	assert.NotContains(t, textContent.Text, "\"body\"")
 }
 
+// Test_ListIssues_AssigneesField covers the assignees field end to end: it is
+// selectable via fields, it is dropped when not requested, and it is always
+// present in an unfiltered response so that "unassigned" reads as [] rather
+// than an absent key.
+func Test_ListIssues_AssigneesField(t *testing.T) {
+	serverTool := ListIssues(translations.NullTranslationHelper)
+
+	callWithFields := func(t *testing.T, fields []any) string {
+		t.Helper()
+		deps := BaseDeps{GQLClient: githubv4.NewClient(listIssuesFieldsMockClient())}
+		handler := serverTool.Handler(deps)
+
+		args := map[string]any{"owner": "owner", "repo": "repo"}
+		if fields != nil {
+			args["fields"] = fields
+		}
+		request := createMCPRequest(args)
+		result, err := handler(ContextWithDeps(context.Background(), deps), &request)
+		require.NoError(t, err)
+		require.False(t, result.IsError)
+		return getTextResult(t, result).Text
+	}
+
+	t.Run("selectable via fields", func(t *testing.T) {
+		var returned struct {
+			Issues []map[string]any `json:"issues"`
+		}
+		require.NoError(t, json.Unmarshal([]byte(callWithFields(t, []any{"number", "assignees"})), &returned))
+		require.Len(t, returned.Issues, 1)
+		require.Len(t, returned.Issues[0], 2, "only the two requested fields should be present")
+		assert.Equal(t, []any{"octocat"}, returned.Issues[0]["assignees"])
+	})
+
+	t.Run("omitted when not requested", func(t *testing.T) {
+		text := callWithFields(t, []any{"number", "title"})
+		assert.NotContains(t, text, "\"assignees\"")
+	})
+
+	t.Run("unassigned issues serialize as an empty array", func(t *testing.T) {
+		// The mock returns one assigned issue, so drive the empty case through
+		// the conversion directly: no assignees node must still yield [], never
+		// null and never an absent key.
+		issue := fragmentToMinimalIssue(IssueFragment{})
+		require.NotNil(t, issue.Assignees)
+
+		encoded, err := json.Marshal(issue)
+		require.NoError(t, err)
+		assert.Contains(t, string(encoded), "\"assignees\":[]")
+	})
+}
+
 func Test_ListIssues_FieldsTelemetry(t *testing.T) {
 	serverTool := ListIssues(translations.NullTranslationHelper)
 

@@ -499,6 +499,12 @@ type IssueFragment struct {
 			Description githubv4.String
 		}
 	} `graphql:"labels(first: 100)"`
+	// GitHub caps issue assignees at 10, so first: 100 cannot truncate.
+	Assignees struct {
+		Nodes []struct {
+			Login githubv4.String
+		}
+	} `graphql:"assignees(first: 100)"`
 	Comments struct {
 		TotalCount githubv4.Int
 	} `graphql:"comments"`