feat: optionally show tool calls in CLI

Author: mokronos

pydantic_ai_slim/pydantic_ai/_cli.py

@@ -18,7 +18,7 @@
 from ._run_context import AgentDepsT
 from .agent import AbstractAgent, Agent
 from .exceptions import UserError
-from .messages import ModelMessage, ModelResponse
+from .messages import FunctionToolCallEvent, FunctionToolResultEvent, ModelMessage, ModelResponse
 from .models import KnownModelName, infer_model
 from .output import OutputDataT
 
@@ -229,6 +229,7 @@ async def run_chat(
     config_dir: Path | None = None,
     deps: AgentDepsT = None,
     message_history: list[ModelMessage] | None = None,
+    show_tool_calls: bool = False,
 ) -> int:
     prompt_history_path = (config_dir or PYDANTIC_AI_HOME) / PROMPT_HISTORY_FILENAME
     prompt_history_path.parent.mkdir(parents=True, exist_ok=True)
@@ -255,7 +256,7 @@ async def run_chat(
                 return exit_value
         else:
             try:
-                messages = await ask_agent(agent, text, stream, console, code_theme, deps, messages)
+                messages = await ask_agent(agent, text, stream, console, code_theme, deps, messages, show_tool_calls)
             except CancelledError:  # pragma: no cover
                 console.print('[dim]Interrupted[/dim]')
             except Exception as e:  # pragma: no cover
@@ -273,6 +274,7 @@ async def ask_agent(
     code_theme: str,
     deps: AgentDepsT = None,
     messages: list[ModelMessage] | None = None,
+    show_tool_calls: bool = False,
 ) -> list[ModelMessage]:
     status = Status('[dim]Working on it…[/dim]', console=console)
 
@@ -294,6 +296,17 @@ async def ask_agent(
 
                         async for content in handle_stream.stream_output(debounce_by=None):
                             live.update(Markdown(str(content), code_theme=code_theme))
+                elif show_tool_calls and Agent.is_call_tools_node(node):
+                    async with node.stream(agent_run.ctx) as handle_stream:
+                        async for event in handle_stream:
+                            if isinstance(event, FunctionToolCallEvent):
+                                console.print(
+                                    Markdown(f'[Tool] {event.part.tool_name!r} called with args={event.part.args}')
+                                )
+                            elif isinstance(event, FunctionToolResultEvent):
+                                console.print(
+                                    Markdown(f'[Tool] {event.result.tool_name!r} returned => {event.result.content}')
+                                )
 
         assert agent_run.result is not None
         return agent_run.result.all_messages()

pydantic_ai_slim/pydantic_ai/agent/abstract.py

@@ -1113,13 +1113,15 @@ async def to_cli(
         deps: AgentDepsT = None,
         prog_name: str = 'pydantic-ai',
         message_history: list[_messages.ModelMessage] | None = None,
+        show_tool_calls: bool = False,
     ) -> None:
         """Run the agent in a CLI chat interface.
 
         Args:
             deps: The dependencies to pass to the agent.
             prog_name: The name of the program to use for the CLI. Defaults to 'pydantic-ai'.
             message_history: History of the conversation so far.
+            show_tool_calls: Whether to show tool calls in the CLI.
 
         Example:
         ```python {title="agent_to_cli.py" test="skip"}
@@ -1143,20 +1145,23 @@ async def main():
             code_theme='monokai',
             prog_name=prog_name,
             message_history=message_history,
+            show_tool_calls=show_tool_calls,
         )
 
     def to_cli_sync(
         self: Self,
         deps: AgentDepsT = None,
         prog_name: str = 'pydantic-ai',
         message_history: list[_messages.ModelMessage] | None = None,
+        show_tool_calls: bool = False,
     ) -> None:
         """Run the agent in a CLI chat interface with the non-async interface.
 
         Args:
             deps: The dependencies to pass to the agent.
             prog_name: The name of the program to use for the CLI. Defaults to 'pydantic-ai'.
             message_history: History of the conversation so far.
+            show_tool_calls: Whether to show tool calls in the CLI.
 
         ```python {title="agent_to_cli_sync.py" test="skip"}
         from pydantic_ai import Agent
@@ -1167,5 +1172,7 @@ def to_cli_sync(
         ```
         """
         return get_event_loop().run_until_complete(
-            self.to_cli(deps=deps, prog_name=prog_name, message_history=message_history)
+            self.to_cli(
+                deps=deps, prog_name=prog_name, message_history=message_history, show_tool_calls=show_tool_calls
+            )
         )

tests/test_cli.py

@@ -293,6 +293,7 @@ def test_agent_to_cli_sync(mocker: MockerFixture, env: TestEnv):
         prog_name='pydantic-ai',
         deps=None,
         message_history=None,
+        show_tool_calls=False,
     )
 
 
@@ -309,6 +310,7 @@ async def test_agent_to_cli_async(mocker: MockerFixture, env: TestEnv):
         prog_name='pydantic-ai',
         deps=None,
         message_history=None,
+        show_tool_calls=False,
     )
 
 
@@ -329,6 +331,7 @@ async def test_agent_to_cli_with_message_history(mocker: MockerFixture, env: Tes
         prog_name='pydantic-ai',
         deps=None,
         message_history=test_messages,
+        show_tool_calls=False,
     )
 
 
@@ -348,4 +351,5 @@ def test_agent_to_cli_sync_with_message_history(mocker: MockerFixture, env: Test
         prog_name='pydantic-ai',
         deps=None,
         message_history=test_messages,
+        show_tool_calls=False,
     )