chat: harden peg-native tool call parsing (#24329)

* chat: harden peg-native tool call parsing

accept an optional leading type: function field in
build_json_tools_flat_keys so openai style tool calls parse on
templates whose serialization opens on the name field.

return a clean error and log the unparsed fragment on a final peg
parse failure instead of throwing the raw parser position and input.

keep the raw arguments string in func_args_not_string when it is not
valid json instead of aborting the prompt render.

* chat: surface peg-native parse failures

a final peg parse failure threw the raw parser position and input. log
the unparsed fragment and raise a clearer error instead, so a model
output that does not match the expected format no longer fails silently
with an empty assistant turn.

minimal change, no behavior change on successful parses.

* chat: handle openai style tool calls in peg-native

* nits

* common: scope OpenAI wrapper grammar trigger via autoparser flag

* chat: gate type:function parsing leniency on the analysis flag

Thread accept_openai_wrapper from the generator to build_json_tools_flat_keys
so the leading "type": "function" field is accepted only when openai_wrapper_trigger is set.

diff --git a/common/chat-auto-parser-generator.cpp b/common/chat-auto-parser-generator.cpp
index 6f825a131bd56835bcd4aba9c334cc8f8c049c6c..37ca55c8dfa3eb0a28b6754347b47031c8c15e6a 100644 (file)
--- a/common/chat-auto-parser-generator.cpp
+++ b/common/chat-auto-parser-generator.cpp
@@ -103,6 +103,10 @@ common_chat_params peg_generator::generate_parser(const common_chat_template &
             data.grammar_triggers = {
                 { COMMON_GRAMMAR_TRIGGER_TYPE_WORD, trigger_marker }
             };
+            if (autoparser.tools.format.openai_wrapper_trigger) {
+                // model emits the OpenAI function wrapper, trigger on it
+                data.grammar_triggers.push_back({ COMMON_GRAMMAR_TRIGGER_TYPE_WORD, "{\"type\": \"function\"," });
+            }
         }
     }
 
@@ -224,13 +228,13 @@ common_peg_parser analyze_tools::build_tool_parser_json_native(parser_build_cont
         auto single_tool_parser = p.standard_json_tools(
             format.per_call_start, format.per_call_end, inputs.tools, inputs.parallel_tool_calls,
             inputs.tool_choice == COMMON_CHAT_TOOL_CHOICE_REQUIRED, name_field, args_field, format.tools_array_wrapped,
-            format.fun_name_is_key, format.id_field, format.gen_id_field, format.parameter_order);
+            format.fun_name_is_key, format.id_field, format.gen_id_field, format.parameter_order, format.openai_wrapper_trigger);
         tools_parser = p.trigger_rule("tool-calls", p.one_or_more(single_tool_parser + p.space()));
     } else {
         tools_parser = p.standard_json_tools(
             format.section_start, format.section_end, inputs.tools, inputs.parallel_tool_calls,
             inputs.tool_choice == COMMON_CHAT_TOOL_CHOICE_REQUIRED, name_field, args_field, format.tools_array_wrapped,
-            format.fun_name_is_key, format.id_field, format.gen_id_field, format.parameter_order);
+            format.fun_name_is_key, format.id_field, format.gen_id_field, format.parameter_order, format.openai_wrapper_trigger);
     }
 
     // Handle content wrappers if present

diff --git a/common/chat-auto-parser.h b/common/chat-auto-parser.h
index 7858f6572f2a870ee5d9b02d17067f2ad9110206..9e8113f24421b83e2837b43cd418e7b4f7001e36 100644 (file)
--- a/common/chat-auto-parser.h
+++ b/common/chat-auto-parser.h
@@ -181,6 +181,7 @@ struct tool_format_analysis {
 
     bool fun_name_is_key = false;       // In JSON format function name is JSON key, i.e. { "<funname>": { ... arguments ... } }
     bool tools_array_wrapped = false;   // Tool calls wrapped in JSON array [...]
+    bool openai_wrapper_trigger = false;  // model emits the OpenAI function wrapper, trigger on it
 
     std::string              function_field = "function";
     std::string              name_field     = "name";

diff --git a/common/chat-diff-analyzer.cpp b/common/chat-diff-analyzer.cpp
index ecd9c807c136d1dca493f9339ca297c79de329d4..b166ee5a18f34b378b4c995aedfd2703846fd64a 100644 (file)
--- a/common/chat-diff-analyzer.cpp
+++ b/common/chat-diff-analyzer.cpp
@@ -165,6 +165,14 @@ static std::vector<std::function<void(const common_chat_template & tmpl, autopar
               LOG_DBG(ANSI_ORANGE "[Patch: Apriel 1.6]\n" ANSI_RESET);
           }
       },
+      // template uses the JSON {name, parameters} tool instruction, emits the OpenAI function wrapper
+      [](const common_chat_template & tmpl, autoparser & analysis) -> void {
+          if (tmpl.src.find("Respond in the format {\"name\": function name") != std::string::npos &&
+              tmpl.src.find("Do not use variables.") != std::string::npos) {
+              analysis.tools.format.openai_wrapper_trigger = true;
+              LOG_DBG(ANSI_ORANGE "[Patch: JSON name/parameters tool instruction]\n" ANSI_RESET);
+          }
+      },
 
     });
 

diff --git a/common/chat-peg-parser.cpp b/common/chat-peg-parser.cpp
index 23b5b384122869826b4b1064765b3e5f2d2b8f13..a3aa765d1c0e87fd650de73e35dcfd95fc817285 100644 (file)
--- a/common/chat-peg-parser.cpp
+++ b/common/chat-peg-parser.cpp
@@ -745,7 +745,8 @@ common_peg_parser common_chat_peg_builder::build_json_tools_flat_keys(
     const std::string &              effective_args_key,
     const std::string &              call_id_key,
     const std::string &              gen_call_id_key,
-    const std::vector<std::string> & parameters_order) {
+    const std::vector<std::string> & parameters_order,
+    bool                             accept_openai_wrapper) {
 
     auto tool_choices    = choice();
     auto name_key_parser = literal("\"" + effective_name_key + "\"");
@@ -807,7 +808,13 @@ common_peg_parser common_chat_peg_builder::build_json_tools_flat_keys(
                 return idx_a < idx_b;
             });
 
-        auto ordered_body = tool_open(literal("{")) + space();
+        // accept an optional leading "type": "function" field when the model emits the OpenAI wrapper
+        common_peg_parser type_field = eps();
+        if (accept_openai_wrapper) {
+            type_field = optional(literal("\"type\"") + space() + literal(":") + space() +
+                                  literal("\"function\"") + space() + literal(",") + space());
+        }
+        auto ordered_body = tool_open(literal("{")) + space() + type_field;
         for (size_t i = 0; i < parser_pairs.size(); i++) {
             ordered_body = ordered_body + parser_pairs[i].first;
             if (i < parser_pairs.size() - 1) {
@@ -870,7 +877,8 @@ common_peg_parser common_chat_peg_builder::standard_json_tools(
                                                        bool                             function_is_key,
                                                        const std::string &              call_id_key,
                                                        const std::string &              gen_call_id_key,
-                                                       const std::vector<std::string> & parameters_order) {
+                                                       const std::vector<std::string> & parameters_order,
+                                                       bool                             accept_openai_wrapper) {
     if (!tools.is_array() || tools.empty()) {
         return eps();
     }
@@ -888,7 +896,7 @@ common_peg_parser common_chat_peg_builder::standard_json_tools(
         if (!name_spec.first.empty() || !args_spec.first.empty()) {
             tool_choices = build_json_tools_nested_keys(tools, effective_name_key, effective_args_key, call_id_key, gen_call_id_key);
         } else {
-            tool_choices = build_json_tools_flat_keys(tools, effective_name_key, effective_args_key, call_id_key, gen_call_id_key, parameters_order);
+            tool_choices = build_json_tools_flat_keys(tools, effective_name_key, effective_args_key, call_id_key, gen_call_id_key, parameters_order, accept_openai_wrapper);
         }
     }
 

diff --git a/common/chat-peg-parser.h b/common/chat-peg-parser.h
index a4643fbea869cdfa87928f29e26398a5d5f05dd2..b3ffd7de2dd8cc3fbdba548ffc4275727e319f8b 100644 (file)
--- a/common/chat-peg-parser.h
+++ b/common/chat-peg-parser.h
@@ -120,7 +120,8 @@ class common_chat_peg_builder : public common_peg_parser_builder {
                                           bool                             function_is_key = false,
                                           const std::string &              call_id_key = "",
                                           const std::string &              gen_call_id_key = "",
-                                          const std::vector<std::string> & parameters_order = {});
+                                          const std::vector<std::string> & parameters_order = {},
+                                          bool                             accept_openai_wrapper = false);
 
     // Legacy-compatible helper for building XML/tagged style tool calls
     // Used by tests and manual parsers
@@ -157,7 +158,8 @@ class common_chat_peg_builder : public common_peg_parser_builder {
                                                  const std::string &              effective_args_key,
                                                  const std::string &              call_id_key,
                                                  const std::string &              gen_call_id_key,
-                                                 const std::vector<std::string> & parameters_order);
+                                                 const std::vector<std::string> & parameters_order,
+                                                 bool                             accept_openai_wrapper);
 };
 
 inline common_peg_arena build_chat_peg_parser(

diff --git a/common/chat.cpp b/common/chat.cpp
index bad53e8b5af2f840458c1dc4697590e8ae115350..05c2e85bee3e7acb2fa2156cec05b83993927dae 100644 (file)
--- a/common/chat.cpp
+++ b/common/chat.cpp
@@ -2678,8 +2678,10 @@ common_chat_msg common_chat_peg_parse(const common_peg_arena &          src_pars
             }
             return msg;
         }
-        throw std::runtime_error(std::string("Failed to parse input at pos ") + std::to_string(result.end) + ": " +
-                                 effective_input.substr(result.end));
+        LOG_WRN("%s: unparsed %s output: %s\n", __func__, common_chat_format_name(params.format),
+                effective_input.substr(result.end).c_str());
+        throw std::runtime_error(std::string("The model produced output that does not match the expected ") +
+                                 common_chat_format_name(params.format) + " format");
     }
 
     common_chat_msg msg;