Files
crewAI/lib/crewai/tests/hooks/test_tool_hooks.py
Lorenze Jay f53bdb28ac feat: implement before and after tool call hooks in CrewAgentExecutor… (#4287)
* feat: implement before and after tool call hooks in CrewAgentExecutor and AgentExecutor

- Added support for before and after tool call hooks in both CrewAgentExecutor and AgentExecutor classes.
- Introduced ToolCallHookContext to manage context for hooks, allowing for enhanced control over tool execution.
- Implemented logic to block tool execution based on before hooks and to modify results based on after hooks.
- Added integration tests to validate the functionality of the new hooks, ensuring they work as expected in various scenarios.
- Enhanced the overall flexibility and extensibility of tool interactions within the CrewAI framework.

* Potential fix for pull request finding 'Unused local variable'

Co-authored-by: Copilot Autofix powered by AI <223894421+github-code-quality[bot]@users.noreply.github.com>

* Potential fix for pull request finding 'Unused local variable'

Co-authored-by: Copilot Autofix powered by AI <223894421+github-code-quality[bot]@users.noreply.github.com>

* test: add integration test for before hook blocking tool execution in Crew

- Implemented a new test to verify that the before hook can successfully block the execution of a tool within a crew.
- The test checks that the tool is not executed when the before hook returns False, ensuring proper control over tool interactions.
- Enhanced the validation of hook calls to confirm that both before and after hooks are triggered appropriately, even when execution is blocked.
- This addition strengthens the testing coverage for tool call hooks in the CrewAI framework.

* drop unused

* refactor(tests): remove OPENAI_API_KEY check from tool hook tests

- Eliminated the check for the OPENAI_API_KEY environment variable in the test cases for tool hooks.
- This change simplifies the test setup and allows for running tests without requiring the API key to be set, improving test accessibility and flexibility.

---------

Co-authored-by: Copilot Autofix powered by AI <223894421+github-code-quality[bot]@users.noreply.github.com>
2026-01-27 14:56:50 -08:00

823 lines
27 KiB
Python

from __future__ import annotations
from unittest.mock import Mock
from crewai.hooks import clear_all_tool_call_hooks, unregister_after_tool_call_hook, unregister_before_tool_call_hook
import pytest
from crewai.hooks.tool_hooks import (
ToolCallHookContext,
get_after_tool_call_hooks,
get_before_tool_call_hooks,
register_after_tool_call_hook,
register_before_tool_call_hook,
)
@pytest.fixture
def mock_tool():
"""Create a mock tool for testing."""
tool = Mock()
tool.name = "test_tool"
tool.description = "Test tool description"
return tool
@pytest.fixture
def mock_agent():
"""Create a mock agent for testing."""
agent = Mock()
agent.role = "Test Agent"
return agent
@pytest.fixture
def mock_task():
"""Create a mock task for testing."""
task = Mock()
task.description = "Test task"
return task
@pytest.fixture
def mock_crew():
"""Create a mock crew for testing."""
crew = Mock()
return crew
@pytest.fixture(autouse=True)
def clear_hooks():
"""Clear global hooks before and after each test."""
from crewai.hooks import tool_hooks
# Store original hooks
original_before = tool_hooks._before_tool_call_hooks.copy()
original_after = tool_hooks._after_tool_call_hooks.copy()
# Clear hooks
tool_hooks._before_tool_call_hooks.clear()
tool_hooks._after_tool_call_hooks.clear()
yield
# Restore original hooks
tool_hooks._before_tool_call_hooks.clear()
tool_hooks._after_tool_call_hooks.clear()
tool_hooks._before_tool_call_hooks.extend(original_before)
tool_hooks._after_tool_call_hooks.extend(original_after)
class TestToolCallHookContext:
"""Test ToolCallHookContext initialization and attributes."""
def test_context_initialization(self, mock_tool, mock_agent, mock_task, mock_crew):
"""Test that context is initialized correctly."""
tool_input = {"arg1": "value1", "arg2": "value2"}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
agent=mock_agent,
task=mock_task,
crew=mock_crew,
)
assert context.tool_name == "test_tool"
assert context.tool_input == tool_input
assert context.tool == mock_tool
assert context.agent == mock_agent
assert context.task == mock_task
assert context.crew == mock_crew
assert context.tool_result is None
def test_context_with_result(self, mock_tool):
"""Test that context includes result when provided."""
tool_input = {"arg1": "value1"}
tool_result = "Test tool result"
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
tool_result=tool_result,
)
assert context.tool_result == tool_result
def test_tool_input_is_mutable_reference(self, mock_tool):
"""Test that modifying context.tool_input modifies the original dict."""
tool_input = {"arg1": "value1"}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
)
# Modify through context
context.tool_input["arg2"] = "value2"
# Check that original dict is also modified
assert "arg2" in tool_input
assert tool_input["arg2"] == "value2"
class TestBeforeToolCallHooks:
"""Test before_tool_call hook registration and execution."""
def test_register_before_hook(self):
"""Test that before hooks are registered correctly."""
def test_hook(context):
return None
register_before_tool_call_hook(test_hook)
hooks = get_before_tool_call_hooks()
assert len(hooks) == 1
assert hooks[0] == test_hook
def test_multiple_before_hooks(self):
"""Test that multiple before hooks can be registered."""
def hook1(context):
return None
def hook2(context):
return None
register_before_tool_call_hook(hook1)
register_before_tool_call_hook(hook2)
hooks = get_before_tool_call_hooks()
assert len(hooks) == 2
assert hook1 in hooks
assert hook2 in hooks
def test_before_hook_can_block_execution(self, mock_tool):
"""Test that before hooks can block tool execution."""
def block_hook(context):
if context.tool_name == "dangerous_tool":
return False # Block execution
return None # Allow execution
tool_input = {}
context = ToolCallHookContext(
tool_name="dangerous_tool",
tool_input=tool_input,
tool=mock_tool,
)
result = block_hook(context)
assert result is False
def test_before_hook_can_allow_execution(self, mock_tool):
"""Test that before hooks can explicitly allow execution."""
def allow_hook(context):
return None # Allow execution
tool_input = {}
context = ToolCallHookContext(
tool_name="safe_tool",
tool_input=tool_input,
tool=mock_tool,
)
result = allow_hook(context)
assert result is None
def test_before_hook_can_modify_input(self, mock_tool):
"""Test that before hooks can modify tool input in-place."""
def modify_input_hook(context):
context.tool_input["modified_by_hook"] = True
return None
tool_input = {"arg1": "value1"}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
)
modify_input_hook(context)
assert "modified_by_hook" in context.tool_input
assert context.tool_input["modified_by_hook"] is True
def test_get_before_hooks_returns_copy(self):
"""Test that get_before_tool_call_hooks returns a copy."""
def test_hook(context):
return None
register_before_tool_call_hook(test_hook)
hooks1 = get_before_tool_call_hooks()
hooks2 = get_before_tool_call_hooks()
# They should be equal but not the same object
assert hooks1 == hooks2
assert hooks1 is not hooks2
class TestAfterToolCallHooks:
"""Test after_tool_call hook registration and execution."""
def test_register_after_hook(self):
"""Test that after hooks are registered correctly."""
def test_hook(context):
return None
register_after_tool_call_hook(test_hook)
hooks = get_after_tool_call_hooks()
assert len(hooks) == 1
assert hooks[0] == test_hook
def test_multiple_after_hooks(self):
"""Test that multiple after hooks can be registered."""
def hook1(context):
return None
def hook2(context):
return None
register_after_tool_call_hook(hook1)
register_after_tool_call_hook(hook2)
hooks = get_after_tool_call_hooks()
assert len(hooks) == 2
assert hook1 in hooks
assert hook2 in hooks
def test_after_hook_can_modify_result(self, mock_tool):
"""Test that after hooks can modify the tool result."""
original_result = "Original result"
def modify_result_hook(context):
if context.tool_result:
return context.tool_result.replace("Original", "Modified")
return None
tool_input = {}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
tool_result=original_result,
)
modified = modify_result_hook(context)
assert modified == "Modified result"
def test_after_hook_returns_none_keeps_original(self, mock_tool):
"""Test that returning None keeps the original result."""
original_result = "Original result"
def no_change_hook(context):
return None
tool_input = {}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
tool_result=original_result,
)
result = no_change_hook(context)
assert result is None
assert context.tool_result == original_result
def test_get_after_hooks_returns_copy(self):
"""Test that get_after_tool_call_hooks returns a copy."""
def test_hook(context):
return None
register_after_tool_call_hook(test_hook)
hooks1 = get_after_tool_call_hooks()
hooks2 = get_after_tool_call_hooks()
# They should be equal but not the same object
assert hooks1 == hooks2
assert hooks1 is not hooks2
class TestToolHooksIntegration:
"""Test integration scenarios with multiple hooks."""
def test_multiple_before_hooks_execute_in_order(self, mock_tool):
"""Test that multiple before hooks execute in registration order."""
execution_order = []
def hook1(context):
execution_order.append(1)
return None
def hook2(context):
execution_order.append(2)
return None
def hook3(context):
execution_order.append(3)
return None
register_before_tool_call_hook(hook1)
register_before_tool_call_hook(hook2)
register_before_tool_call_hook(hook3)
tool_input = {}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
)
hooks = get_before_tool_call_hooks()
for hook in hooks:
hook(context)
assert execution_order == [1, 2, 3]
def test_first_blocking_hook_stops_execution(self, mock_tool):
"""Test that first hook returning False blocks execution."""
execution_order = []
def hook1(context):
execution_order.append(1)
return None # Allow
def hook2(context):
execution_order.append(2)
return False # Block
def hook3(context):
execution_order.append(3)
return None # This shouldn't run
register_before_tool_call_hook(hook1)
register_before_tool_call_hook(hook2)
register_before_tool_call_hook(hook3)
tool_input = {}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
)
hooks = get_before_tool_call_hooks()
blocked = False
for hook in hooks:
result = hook(context)
if result is False:
blocked = True
break
assert blocked is True
assert execution_order == [1, 2] # hook3 didn't run
def test_multiple_after_hooks_chain_modifications(self, mock_tool):
"""Test that multiple after hooks can chain modifications."""
def hook1(context):
if context.tool_result:
return context.tool_result + " [hook1]"
return None
def hook2(context):
if context.tool_result:
return context.tool_result + " [hook2]"
return None
register_after_tool_call_hook(hook1)
register_after_tool_call_hook(hook2)
tool_input = {}
context = ToolCallHookContext(
tool_name="test_tool",
tool_input=tool_input,
tool=mock_tool,
tool_result="Original",
)
hooks = get_after_tool_call_hooks()
# Simulate chaining (how it would be used in practice)
result = context.tool_result
for hook in hooks:
# Update context for next hook
context.tool_result = result
modified = hook(context)
if modified is not None:
result = modified
assert result == "Original [hook1] [hook2]"
def test_hooks_with_validation_and_sanitization(self, mock_tool):
"""Test a realistic scenario with validation and sanitization hooks."""
# Validation hook (before)
def validate_file_path(context):
if context.tool_name == "write_file":
file_path = context.tool_input.get("file_path", "")
if ".env" in file_path:
return False # Block sensitive files
return None
# Sanitization hook (after)
def sanitize_secrets(context):
if context.tool_result and "SECRET_KEY" in context.tool_result:
return context.tool_result.replace("SECRET_KEY=abc123", "SECRET_KEY=[REDACTED]")
return None
register_before_tool_call_hook(validate_file_path)
register_after_tool_call_hook(sanitize_secrets)
# Test blocking
blocked_context = ToolCallHookContext(
tool_name="write_file",
tool_input={"file_path": ".env"},
tool=mock_tool,
)
before_hooks = get_before_tool_call_hooks()
blocked = False
for hook in before_hooks:
if hook(blocked_context) is False:
blocked = True
break
assert blocked is True
# Test sanitization
sanitize_context = ToolCallHookContext(
tool_name="read_file",
tool_input={"file_path": "config.txt"},
tool=mock_tool,
tool_result="Content: SECRET_KEY=abc123",
)
after_hooks = get_after_tool_call_hooks()
result = sanitize_context.tool_result
for hook in after_hooks:
sanitize_context.tool_result = result
modified = hook(sanitize_context)
if modified is not None:
result = modified
assert "SECRET_KEY=[REDACTED]" in result
assert "abc123" not in result
def test_unregister_before_hook(self):
"""Test that before hooks can be unregistered."""
def test_hook(context):
pass
register_before_tool_call_hook(test_hook)
unregister_before_tool_call_hook(test_hook)
hooks = get_before_tool_call_hooks()
assert len(hooks) == 0
def test_unregister_after_hook(self):
"""Test that after hooks can be unregistered."""
def test_hook(context):
return None
register_after_tool_call_hook(test_hook)
unregister_after_tool_call_hook(test_hook)
hooks = get_after_tool_call_hooks()
assert len(hooks) == 0
def test_clear_all_tool_call_hooks(self):
"""Test that all tool call hooks can be cleared."""
def test_hook(context):
pass
register_before_tool_call_hook(test_hook)
register_after_tool_call_hook(test_hook)
clear_all_tool_call_hooks()
hooks = get_before_tool_call_hooks()
assert len(hooks) == 0
@pytest.mark.vcr()
def test_lite_agent_hooks_integration_with_real_tool(self):
"""Test that LiteAgent executes before/after tool call hooks with real tool calls."""
import os
from crewai.lite_agent import LiteAgent
from crewai.tools import tool
# Skip if no API key available
if not os.environ.get("OPENAI_API_KEY"):
pytest.skip("OPENAI_API_KEY not set - skipping real tool test")
# Track hook invocations
hook_calls = {"before": [], "after": []}
# Create a simple test tool
@tool("calculate_sum")
def calculate_sum(a: int, b: int) -> int:
"""Add two numbers together."""
return a + b
def before_tool_call_hook(context: ToolCallHookContext) -> bool:
"""Log and verify before hook execution."""
print(f"\n[BEFORE HOOK] Tool: {context.tool_name}")
print(f"[BEFORE HOOK] Tool input: {context.tool_input}")
print(f"[BEFORE HOOK] Agent: {context.agent.role if context.agent else 'None'}")
print(f"[BEFORE HOOK] Task: {context.task}")
print(f"[BEFORE HOOK] Crew: {context.crew}")
# Track the call
hook_calls["before"].append({
"tool_name": context.tool_name,
"tool_input": context.tool_input,
"has_agent": context.agent is not None,
"has_task": context.task is not None,
"has_crew": context.crew is not None,
})
return True # Allow execution
def after_tool_call_hook(context: ToolCallHookContext) -> str | None:
"""Log and verify after hook execution."""
print(f"\n[AFTER HOOK] Tool: {context.tool_name}")
print(f"[AFTER HOOK] Tool result: {context.tool_result}")
print(f"[AFTER HOOK] Agent: {context.agent.role if context.agent else 'None'}")
# Track the call
hook_calls["after"].append({
"tool_name": context.tool_name,
"tool_result": context.tool_result,
"has_result": context.tool_result is not None,
})
return None # Don't modify result
# Register hooks
register_before_tool_call_hook(before_tool_call_hook)
register_after_tool_call_hook(after_tool_call_hook)
try:
# Create LiteAgent with the tool
lite_agent = LiteAgent(
role="Calculator Assistant",
goal="Help with math calculations",
backstory="You are a helpful calculator assistant",
tools=[calculate_sum],
verbose=True,
)
# Execute with a prompt that should trigger tool usage
result = lite_agent.kickoff("What is 5 + 3? Use the calculate_sum tool.")
# Verify hooks were called
assert len(hook_calls["before"]) > 0, "Before hook was never called"
assert len(hook_calls["after"]) > 0, "After hook was never called"
# Verify context had correct attributes for LiteAgent (used in flows)
# LiteAgent doesn't have task/crew context, unlike agents in CrewBase
before_call = hook_calls["before"][0]
assert before_call["tool_name"] == "calculate_sum", "Tool name should be 'calculate_sum'"
assert "a" in before_call["tool_input"], "Tool input should have 'a' parameter"
assert "b" in before_call["tool_input"], "Tool input should have 'b' parameter"
# Verify after hook received result
after_call = hook_calls["after"][0]
assert after_call["has_result"] is True, "After hook should have tool result"
assert after_call["tool_name"] == "calculate_sum", "Tool name should match"
# The result should contain the sum (8)
assert "8" in str(after_call["tool_result"]), "Tool result should contain the sum"
finally:
# Clean up hooks
unregister_before_tool_call_hook(before_tool_call_hook)
unregister_after_tool_call_hook(after_tool_call_hook)
class TestNativeToolCallingHooksIntegration:
"""Integration tests for hooks with native function calling (Agent and Crew)."""
@pytest.mark.vcr()
def test_agent_native_tool_hooks_before_and_after(self):
"""Test that Agent with native tool calling executes before/after hooks."""
import os
from crewai import Agent
from crewai.tools import tool
hook_calls = {"before": [], "after": []}
@tool("multiply_numbers")
def multiply_numbers(a: int, b: int) -> int:
"""Multiply two numbers together."""
return a * b
def before_hook(context: ToolCallHookContext) -> bool | None:
hook_calls["before"].append({
"tool_name": context.tool_name,
"tool_input": dict(context.tool_input),
"has_agent": context.agent is not None,
})
return None
def after_hook(context: ToolCallHookContext) -> str | None:
hook_calls["after"].append({
"tool_name": context.tool_name,
"tool_result": context.tool_result,
"has_agent": context.agent is not None,
})
return None
register_before_tool_call_hook(before_hook)
register_after_tool_call_hook(after_hook)
try:
agent = Agent(
role="Calculator",
goal="Perform calculations",
backstory="You are a calculator assistant",
tools=[multiply_numbers],
verbose=True,
)
agent.kickoff(
messages="What is 7 times 6? Use the multiply_numbers tool."
)
# Verify before hook was called
assert len(hook_calls["before"]) > 0, "Before hook was never called"
before_call = hook_calls["before"][0]
assert before_call["tool_name"] == "multiply_numbers"
assert "a" in before_call["tool_input"]
assert "b" in before_call["tool_input"]
assert before_call["has_agent"] is True
# Verify after hook was called
assert len(hook_calls["after"]) > 0, "After hook was never called"
after_call = hook_calls["after"][0]
assert after_call["tool_name"] == "multiply_numbers"
assert "42" in str(after_call["tool_result"])
assert after_call["has_agent"] is True
finally:
unregister_before_tool_call_hook(before_hook)
unregister_after_tool_call_hook(after_hook)
@pytest.mark.vcr()
def test_crew_native_tool_hooks_before_and_after(self):
"""Test that Crew with Agent executes before/after hooks with full context."""
import os
from crewai import Agent, Crew, Task
from crewai.tools import tool
hook_calls = {"before": [], "after": []}
@tool("divide_numbers")
def divide_numbers(a: int, b: int) -> float:
"""Divide first number by second number."""
return a / b
def before_hook(context: ToolCallHookContext) -> bool | None:
hook_calls["before"].append({
"tool_name": context.tool_name,
"tool_input": dict(context.tool_input),
"has_agent": context.agent is not None,
"has_task": context.task is not None,
"has_crew": context.crew is not None,
"agent_role": context.agent.role if context.agent else None,
})
return None
def after_hook(context: ToolCallHookContext) -> str | None:
hook_calls["after"].append({
"tool_name": context.tool_name,
"tool_result": context.tool_result,
"has_agent": context.agent is not None,
"has_task": context.task is not None,
"has_crew": context.crew is not None,
})
return None
register_before_tool_call_hook(before_hook)
register_after_tool_call_hook(after_hook)
try:
agent = Agent(
role="Math Assistant",
goal="Perform division calculations accurately",
backstory="You are a math assistant that helps with division",
tools=[divide_numbers],
verbose=True,
)
task = Task(
description="Calculate 100 divided by 4 using the divide_numbers tool.",
expected_output="The result of the division",
agent=agent,
)
crew = Crew(
agents=[agent],
tasks=[task],
verbose=True,
)
crew.kickoff()
# Verify before hook was called with full context
assert len(hook_calls["before"]) > 0, "Before hook was never called"
before_call = hook_calls["before"][0]
assert before_call["tool_name"] == "divide_numbers"
assert "a" in before_call["tool_input"]
assert "b" in before_call["tool_input"]
assert before_call["has_agent"] is True
assert before_call["has_task"] is True
assert before_call["has_crew"] is True
assert before_call["agent_role"] == "Math Assistant"
# Verify after hook was called with full context
assert len(hook_calls["after"]) > 0, "After hook was never called"
after_call = hook_calls["after"][0]
assert after_call["tool_name"] == "divide_numbers"
assert "25" in str(after_call["tool_result"])
assert after_call["has_agent"] is True
assert after_call["has_task"] is True
assert after_call["has_crew"] is True
finally:
unregister_before_tool_call_hook(before_hook)
unregister_after_tool_call_hook(after_hook)
@pytest.mark.vcr()
def test_before_hook_blocks_tool_execution_in_crew(self):
"""Test that returning False from before hook blocks tool execution."""
import os
from crewai import Agent, Crew, Task
from crewai.tools import tool
hook_calls = {"before": [], "after": [], "tool_executed": False}
@tool("dangerous_operation")
def dangerous_operation(action: str) -> str:
"""Perform a dangerous operation that should be blocked."""
hook_calls["tool_executed"] = True
return f"Executed: {action}"
def blocking_before_hook(context: ToolCallHookContext) -> bool | None:
hook_calls["before"].append({
"tool_name": context.tool_name,
"tool_input": dict(context.tool_input),
})
# Block all calls to dangerous_operation
if context.tool_name == "dangerous_operation":
return False
return None
def after_hook(context: ToolCallHookContext) -> str | None:
hook_calls["after"].append({
"tool_name": context.tool_name,
"tool_result": context.tool_result,
})
return None
register_before_tool_call_hook(blocking_before_hook)
register_after_tool_call_hook(after_hook)
try:
agent = Agent(
role="Test Agent",
goal="Try to use the dangerous operation tool",
backstory="You are a test agent",
tools=[dangerous_operation],
verbose=True,
)
task = Task(
description="Use the dangerous_operation tool with action 'delete_all'.",
expected_output="The result of the operation",
agent=agent,
)
crew = Crew(
agents=[agent],
tasks=[task],
verbose=True,
)
crew.kickoff()
# Verify before hook was called
assert len(hook_calls["before"]) > 0, "Before hook was never called"
before_call = hook_calls["before"][0]
assert before_call["tool_name"] == "dangerous_operation"
# Verify the actual tool function was NOT executed
assert hook_calls["tool_executed"] is False, "Tool should have been blocked"
# Verify after hook was still called (with blocked message)
assert len(hook_calls["after"]) > 0, "After hook was never called"
after_call = hook_calls["after"][0]
assert "blocked" in after_call["tool_result"].lower()
finally:
unregister_before_tool_call_hook(blocking_before_hook)
unregister_after_tool_call_hook(after_hook)