Add support for bare function calls in tool call recovery

Author: YingchaoX

internal/defaults/defaults.go

@@ -11,6 +11,17 @@ CORE BEHAVIOR
 - Reply in the same language as the user unless explicitly asked otherwise.
 - Always obey constraints declared in [RUNTIME_MODE]. If any instruction conflicts, [RUNTIME_MODE] wins.
 
+TOOL CALLING (OPENAI-COMPATIBLE)
+- When tools are provided in the request, you MUST invoke them via OpenAI-style tool_calls (functions) instead of encoding tool usage inside assistant content.
+- For every tool invocation, populate the tool_calls list with:
+  - type = "function"
+  - function.name set to the tool name
+  - function.arguments as a strict JSON object containing only the arguments for that tool.
+- Assistant message content (the "content" field) MUST NOT contain surrogate tool markup such as <tool_call>, <function=...>, <parameter=...>, XML-like tags, or JSON blobs that represent tool calls.
+- Natural language in "content" should describe your reasoning, next steps, and results. Use tool_calls as the ONLY channel to actually invoke tools.
+- If no tools are provided, answer normally and do NOT fabricate tool_calls.
+- These rules apply regardless of the underlying model provider; always follow this contract when tools are present.
+
 REQUEST TRIAGE (AVOID OVER-PLANNING)
 - Classify the request before acting:
   - Utility/factual request (e.g., time, timezone, conversion, quick calculation, one-off command output).

internal/orchestrator/orchestrator_test.go

@@ -856,6 +856,26 @@ func TestRecoverToolCallsFromContent_TaggedFunction(t *testing.T) {
 	}
 }
 
+func TestRecoverToolCallsFromContent_BareTaggedFunction(t *testing.T) {
+	content := "I'll help you install Python.\n<function=bash>\n<parameter=command>\nuname -s\n</parameter>\n</function>\n</tool_call>"
+	defs := []chat.ToolDef{
+		{Type: "function", Function: chat.ToolFunction{Name: "bash", Parameters: map[string]any{"type": "object"}}},
+	}
+	calls, cleaned := recoverToolCallsFromContent(content, defs)
+	if len(calls) != 1 {
+		t.Fatalf("recovered calls=%d, want 1", len(calls))
+	}
+	if calls[0].Function.Name != "bash" {
+		t.Fatalf("unexpected tool name: %+v", calls[0])
+	}
+	if calls[0].Function.Arguments != `{"command":"uname -s"}` {
+		t.Fatalf("unexpected args: %s", calls[0].Function.Arguments)
+	}
+	if strings.Contains(cleaned, "<function=bash>") {
+		t.Fatalf("expected cleaned content without function block, got %q", cleaned)
+	}
+}
+
 func TestRecoverToolCallsFromContent_JSONStyle(t *testing.T) {
 	content := "<tool_call>{\"name\":\"bash\",\"arguments\":{\"command\":\"uname -a\"}}</tool_call>"
 	defs := []chat.ToolDef{

internal/orchestrator/toolcall_recovery.go

@@ -37,7 +37,9 @@ func recoverToolCallsFromContent(content string, defs []chat.ToolDef) ([]chat.To
 
 	matches := toolCallBlockPattern.FindAllStringSubmatchIndex(content, -1)
 	if len(matches) == 0 {
-		return nil, content
+		// 一些模型（例如部分 Qwen 兼容服务）可能只输出裸露的 <function=...> 标签，
+		// 而不会包在 <tool_call>...</tool_call> 块里。为保持兼容性，这里做一次降级恢复。
+		return recoverBareFunctionCallsFromContent(content, allowed)
 	}
 
 	calls := make([]chat.ToolCall, 0, len(matches))
@@ -110,6 +112,45 @@ func parseJSONStyleToolCall(inner string, allowed map[string]struct{}, seq int)
 	}, true
 }
 
+// recoverBareFunctionCallsFromContent 处理没有显式 <tool_call> 包裹的 <function=...> 块。
+// 例如：
+// <function=bash>
+// <parameter=command>
+// uname -s
+// </parameter>
+// </function>
+func recoverBareFunctionCallsFromContent(content string, allowed map[string]struct{}) ([]chat.ToolCall, string) {
+	matches := functionCallPattern.FindAllStringSubmatchIndex(content, -1)
+	if len(matches) == 0 {
+		return nil, content
+	}
+
+	calls := make([]chat.ToolCall, 0, len(matches))
+	var cleaned strings.Builder
+	last := 0
+
+	for i, m := range matches {
+		if len(m) < 2 {
+			continue
+		}
+		start, end := m[0], m[1]
+		// 保留前面的普通文本
+		cleaned.WriteString(content[last:start])
+		last = end
+
+		snippet := strings.TrimSpace(content[start:end])
+		call, ok := parseTaggedFunctionToolCall(snippet, allowed, i+1)
+		if !ok {
+			// 无法解析时保留原始片段，避免丢信息
+			cleaned.WriteString(content[start:end])
+			continue
+		}
+		calls = append(calls, call)
+	}
+	cleaned.WriteString(content[last:])
+	return calls, strings.TrimSpace(cleaned.String())
+}
+
 func parseTaggedFunctionToolCall(inner string, allowed map[string]struct{}, seq int) (chat.ToolCall, bool) {
 	m := functionCallPattern.FindStringSubmatch(inner)
 	if len(m) != 3 {