feat: integrate poka-yoke validation into tool dispatch (#836)

- Added import for tool_pokayoke module
- Added validation before orchestrator.dispatch calls
- Auto-corrects tool names and parameters
- Returns structured errors with suggestions
- Circuit breaker for consecutive failures

Closes #836

model_tools.py

@@ -27,6 +27,7 @@ import threading
 from typing import Dict, Any, List, Optional, Tuple
 
 from tools.registry import discover_builtin_tools, registry
+from tools.tool_pokayoke import validate_tool_call, reset_circuit_breaker, get_hallucination_stats
 from toolsets import resolve_toolset, validate_toolset
 from agent.tool_orchestrator import orchestrator
 
@@ -500,6 +501,32 @@ def handle_function_call(
             # Prefer the caller-provided list so subagents can't overwrite
             # the parent's tool set via the process-global.
             sandbox_enabled = enabled_tools if enabled_tools is not None else _last_resolved_tool_names
+            # Poka-yoke: validate tool call before dispatch
+            is_valid, corrected_name, corrected_params, pokayoke_messages = validate_tool_call(function_name, function_args)
+            if not is_valid:
+                # Return structured error with suggestions
+                error_msg = "\n".join(pokayoke_messages)
+                logger.warning(f"Poka-yoke blocked: {function_name} - {error_msg}")
+                return json.dumps({"error": error_msg, "pokayoke": True, "tool_name": function_name})
+            if corrected_name:
+                function_name = corrected_name
+            if corrected_params:
+                function_args = corrected_params
+            if pokayoke_messages:
+                logger.info(f"Poka-yoke: {pokayoke_messages}")
+            # Poka-yoke: validate tool call before dispatch (else branch)
+            is_valid, corrected_name, corrected_params, pokayoke_messages = validate_tool_call(function_name, function_args)
+            if not is_valid:
+                # Return structured error with suggestions
+                error_msg = "\n".join(pokayoke_messages)
+                logger.warning(f"Poka-yoke blocked: {function_name} - {error_msg}")
+                return json.dumps({"error": error_msg, "pokayoke": True, "tool_name": function_name})
+            if corrected_name:
+                function_name = corrected_name
+            if corrected_params:
+                function_args = corrected_params
+            if pokayoke_messages:
+                logger.info(f"Poka-yoke: {pokayoke_messages}")
             result = orchestrator.dispatch(
                 function_name, function_args,
                 task_id=task_id,