Merge pull request #980 from dpersek/fix/tools-list-pagination-971

Fix tools/list default pagination for non-paginating clients

Author: DeusData

src/mcp/mcp.c

@@ -621,7 +621,10 @@ const char *cbm_mcp_tool_input_schema(const char *tool_name) {
     return NULL;
 }
 
-static int mcp_tools_cursor_offset(const char *params_json) {
+static int mcp_tools_cursor_offset(const char *params_json, bool *has_cursor_out) {
+    if (has_cursor_out) {
+        *has_cursor_out = false;
+    }
     if (!params_json) {
         return 0;
     }
@@ -635,6 +638,9 @@ static int mcp_tools_cursor_offset(const char *params_json) {
     yyjson_val *root = yyjson_doc_get_root(doc);
     yyjson_val *cursor = root ? yyjson_obj_get(root, "cursor") : NULL;
     if (cursor) {
+        if (has_cursor_out) {
+            *has_cursor_out = true;
+        }
         offset = TOOL_COUNT;
         if (yyjson_is_str(cursor)) {
             const char *cursor_str = yyjson_get_str(cursor);
@@ -654,8 +660,12 @@ static int mcp_tools_cursor_offset(const char *params_json) {
 }
 
 static char *cbm_mcp_tools_list_page(const char *params_json) {
-    return cbm_mcp_tools_list_range(mcp_tools_cursor_offset(params_json), MCP_TOOLS_PAGE_SIZE,
-                                    true);
+    bool has_cursor = false;
+    int offset = mcp_tools_cursor_offset(params_json, &has_cursor);
+    if (!has_cursor) {
+        return cbm_mcp_tools_list();
+    }
+    return cbm_mcp_tools_list_range(offset, MCP_TOOLS_PAGE_SIZE, true);
 }
 
 /* Supported protocol versions, newest first. The server picks the newest

tests/test_mcp.c

@@ -586,16 +586,26 @@ TEST(server_handle_tools_list) {
     PASS();
 }
 
-TEST(server_handle_tools_list_paginates) {
+TEST(server_handle_tools_list_defaults_to_all_tools_and_accepts_cursor) {
     cbm_mcp_server_t *srv = cbm_mcp_server_new(NULL);
 
     char *resp =
         cbm_mcp_server_handle(srv, "{\"jsonrpc\":\"2.0\",\"id\":200,\"method\":\"tools/list\"}");
     ASSERT_NOT_NULL(resp);
     ASSERT_NOT_NULL(strstr(resp, "\"id\":200"));
-    ASSERT_NOT_NULL(strstr(resp, "\"nextCursor\":\"8\""));
+    ASSERT_NULL(strstr(resp, "\"nextCursor\""));
     ASSERT_NOT_NULL(strstr(resp, "index_repository"));
-    ASSERT_NULL(strstr(resp, "manage_adr"));
+    ASSERT_NOT_NULL(strstr(resp, "manage_adr"));
+    ASSERT_NOT_NULL(strstr(resp, "ingest_traces"));
+    free(resp);
+
+    resp = cbm_mcp_server_handle(
+        srv, "{\"jsonrpc\":\"2.0\",\"id\":202,\"method\":\"tools/list\",\"params\":{}}");
+    ASSERT_NOT_NULL(resp);
+    ASSERT_NOT_NULL(strstr(resp, "\"id\":202"));
+    ASSERT_NULL(strstr(resp, "\"nextCursor\""));
+    ASSERT_NOT_NULL(strstr(resp, "manage_adr"));
+    ASSERT_NOT_NULL(strstr(resp, "ingest_traces"));
     free(resp);
 
     resp = cbm_mcp_server_handle(
@@ -5238,7 +5248,7 @@ SUITE(mcp) {
     RUN_TEST(server_handle_initialize);
     RUN_TEST(server_handle_initialized_notification);
     RUN_TEST(server_handle_tools_list);
-    RUN_TEST(server_handle_tools_list_paginates);
+    RUN_TEST(server_handle_tools_list_defaults_to_all_tools_and_accepts_cursor);
     RUN_TEST(server_handle_logs_request_without_params);
     RUN_TEST(server_handle_unknown_method);