feat: add tool support for the agent

src/fenn/agents/agent.py

@@ -1,5 +1,6 @@
 from fenn.agents import Flow
 from fenn.agents.node import ThinkNode, ActNode, ObserveNode
+from fenn.agents.tools import get_tool_schema
 import yaml
 
 class Agent:
@@ -27,6 +28,7 @@ def run(self, user_input):
                 {"role": "system", "content": self.config["agent"]["system_prompt"]},
                 {"role": "user",   "content": user_input}
             ],
+            "tools": get_tool_schema(),
             "iterations": 0,
             "max_iterations": self.config["agent"]["max_iterations"],
             "last_thought": None,

src/fenn/agents/node.py

@@ -1,5 +1,5 @@
 from fenn.agents import Node
-from fenn.agents.tools import TOOLS
+from fenn.agents.tools import execute_tool
 
 class ThinkNode(Node):
     def prep(self, shared):
@@ -22,13 +22,20 @@ def prep(self, shared):
         return shared["last_thought"]
 
     def exec(self, thought):
-        line = [l for l in thought.split("\n") if l.startswith("Action:")][0]
-        tool_call = line.replace("Action:", "").strip()
+        if "Action:" in thought:
+            line = [l for l in thought.split("\n") if l.startswith("Action:")][0]
+            tool_call = line.replace("Action:", "").strip()
+        else:
+            tool_call = thought.strip()
 
         tool_name = tool_call.split("(")[0]
-        tool_arg  = tool_call.split("(")[1].rstrip(")")
+        args_str = tool_call.split("(")[1].rstrip(")")
+        tool_args = [arg.strip() for arg in args_str.split(",")]
 
-        result = TOOLS[tool_name](tool_arg)
+        try:
+            result = execute_tool(tool_name, *tool_args)
+        except Exception as e:
+            result = f"Error: {e}"
         return result
 
     def post(self, shared, prep_res, exec_res):

src/fenn/agents/tools.py

@@ -1,10 +1,32 @@
-TOOLS = {
-    "search": lambda query: f"Search result for: {query}",
-    "calculator": lambda expr: str(eval(expr))
-}
-
-# This is what you put in the LLM prompt so it knows what tools exist
-TOOL_DESCRIPTIONS = """
-- search(query): Search the web
-- calculator(expr): Evaluate a math expression
-"""
+import inspect
+from functools import wraps
+from typing import Dict, Any
+
+TOOLS_REGISTRY: Dict[str, Dict[str, Any]] = {}
+
+def tool(func):
+    """
+    A decorator that registers an executable function as a tool
+    """
+    @wraps(func)
+    def decorator(*args, **kwargs):
+        return func(*args, **kwargs)
+    tool_name = func.__name__
+    tools_description = inspect.getdoc(func) or "No description provided"
+
+    TOOLS_REGISTRY[tool_name] = {
+        "schema": {
+            "name": tool_name,
+            "description": tools_description
+        },
+        "execute": func
+    }
+    return decorator
+
+def get_tool_schema():
+    return [info["schema"] for info in TOOLS_REGISTRY.values()]
+
+def execute_tool(name: str, *args, **kwargs):
+    if name not in TOOLS_REGISTRY:
+        raise ValueError(f"Tool '{name}' is not registered.")
+    return TOOLS_REGISTRY[name]["execute"](*args, **kwargs)