Files
crewAI/lib/crewai-tools
João Moura 97981ed31b
Some checks failed
CodeQL Advanced / Analyze (actions) (push) Has been cancelled
CodeQL Advanced / Analyze (python) (push) Has been cancelled
Check Documentation Broken Links / Check broken links (push) Has been cancelled
Vulnerability Scan / pip-audit (push) Has been cancelled
feat(tools): add WaitTool for pausing on long-running jobs (#6690)
* feat(tools): add WaitTool for pausing on long-running jobs

Agents that kick off out-of-band work (a sandbox build, a deployment, an
async API job) have no way to let clock time pass: they either poll in a
tight loop or give up before the work finishes.

WaitTool pauses for a given number of seconds, with an optional reason
echoed back for traces. A single call waits at most max_seconds (default
300, configurable). Longer requests are clamped to the cap and the result
says so, so the model calls again rather than failing. Sync and async
execution are both implemented; stdlib only, no new dependencies.

The tool description spells out when to reach for it (builds, deploys,
batch jobs, async polling, backoff) and when not to, so models pick it up
for the right reason.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* fix(tools): enforce non-negative wait on positional calls, fix doc snippets

BaseTool.run() skips args_schema validation when called with positional
arguments, so tool.run(-5) reached time.sleep(-5) and failed with an
unrelated error. _resolve_duration now enforces the seconds >= 0 contract
itself, covered for both run() and arun().

Docs and README examples are now self-contained: check_build_status_tool
is defined with the @tool decorator instead of referenced out of nowhere,
and the async example awaits inside asyncio.run() rather than at top level.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* docs: point the wait tool card at the edge path

Unprefixed links resolve against the default docs version (v1.15.7),
where the wait tool page does not exist, so the card 404'd in the broken
link check. Prefixing with /edge matches how other edge pages link.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* fix(tools): never cache waits and keep the advertised cap accurate

Two issues from review, both confirmed against the code.

Waits inherited the default cache_function, which always allows caching.
With crew cache enabled, a repeat call with the same arguments returned
"Waited N seconds." straight from the cache without sleeping, turning a
poll-wait-check loop into a busy loop. WaitTool now declares a
cache_function that always refuses.

The description advertising the cap was only rebuilt when max_seconds
reached __init__ without an explicit description. Passing both (as a
platform building from tool.specs.json init params would), calling
model_validate, or assigning max_seconds left the text claiming 300
seconds while clamping to something else. A model_validator now derives
the description from max_seconds on construction, validation, and
assignment, and leaves a caller-supplied description untouched.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* fix(tools): reject NaN waits and pluralize single-second results

_resolve_duration now rejects NaN with its own message instead of letting
time.sleep raise "Invalid value NaN (not a number)" from a positional
call. Infinity keeps clamping to the cap like any other oversized wait.

Result and description text no longer says "1 seconds". Tests use the
public WaitTool().description as the baseline rather than reaching for
module-private helpers.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-27 17:12:27 -07:00
..

Logo of crewAI, two people rowing on a boat

CrewAI Tools

Empower your CrewAI agents with powerful, customizable tools to elevate their capabilities and tackle sophisticated, real-world tasks.

CrewAI Tools provide the essential functionality to extend your agents, helping you rapidly enhance your automations with reliable, ready-to-use tools or custom-built solutions tailored precisely to your needs.


Homepage | Documentation | Examples | Community


Available Tools

CrewAI provides an extensive collection of powerful tools ready to enhance your agents:

  • File Management: FileReadTool, FileWriteTool
  • Web Scraping: ScrapeWebsiteTool, SeleniumScrapingTool
  • Database Integrations: MySQLSearchTool
  • Vector Database Integrations: MongoDBVectorSearchTool, QdrantVectorSearchTool, WeaviateVectorSearchTool
  • API Integrations: SerperApiTool, ExaSearchTool
  • AI-powered Tools: DallETool, VisionTool, StagehandTool

And many more robust tools to simplify your agent integrations.


Creating Custom Tools

CrewAI offers two straightforward approaches to creating custom tools:

Subclassing BaseTool

Define your tool by subclassing:

from crewai.tools import BaseTool

class MyCustomTool(BaseTool):
    name: str = "Tool Name"
    description: str = "Detailed description here."

    def _run(self, *args, **kwargs):
        # Your tool logic here

Using the tool Decorator

Quickly create lightweight tools using decorators:

from crewai import tool

@tool("Tool Name")
def my_custom_function(input):
    # Tool logic here
    return output

CrewAI Tools and MCP

CrewAI Tools supports the Model Context Protocol (MCP). It gives you access to thousands of tools from the hundreds of MCP servers out there built by the community.

Before you start using MCP with CrewAI tools, you need to install the mcp extra dependencies:

pip install crewai-tools[mcp]
# or
uv add crewai-tools --extra mcp

To quickly get started with MCP in CrewAI you have 2 options:

Option 1: Fully managed connection

In this scenario we use a contextmanager (with statement) to start and stop the the connection with the MCP server. This is done in the background and you only get to interact with the CrewAI tools corresponding to the MCP server's tools.

For an STDIO based MCP server:

from mcp import StdioServerParameters
from crewai_tools import MCPServerAdapter

serverparams = StdioServerParameters(
    command="uvx",
    args=["--quiet", "pubmedmcp@0.1.3"],
    env={"UV_PYTHON": "3.12", **os.environ},
)

with MCPServerAdapter(serverparams) as tools:
    # tools is now a list of CrewAI Tools matching 1:1 with the MCP server's tools
    agent = Agent(..., tools=tools)
    task = Task(...)
    crew = Crew(..., agents=[agent], tasks=[task])
    crew.kickoff(...)

For an SSE based MCP server:

serverparams = {"url": "http://localhost:8000/sse"}
with MCPServerAdapter(serverparams) as tools:
    # tools is now a list of CrewAI Tools matching 1:1 with the MCP server's tools
    agent = Agent(..., tools=tools)
    task = Task(...)
    crew = Crew(..., agents=[agent], tasks=[task])
    crew.kickoff(...)

Option 2: More control over the MCP connection

If you need more control over the MCP connection, you can instanciate the MCPServerAdapter into an mcp_server_adapter object which can be used to manage the connection with the MCP server and access the available tools.

important: in this case you need to call mcp_server_adapter.stop() to make sure the connection is correctly stopped. We recommend that you use a try ... finally block run to make sure the .stop() is called even in case of errors.

Here is the same example for an STDIO MCP Server:

from mcp import StdioServerParameters
from crewai_tools import MCPServerAdapter

serverparams = StdioServerParameters(
    command="uvx",
    args=["--quiet", "pubmedmcp@0.1.3"],
    env={"UV_PYTHON": "3.12", **os.environ},
)

try:
    mcp_server_adapter = MCPServerAdapter(serverparams)
    tools = mcp_server_adapter.tools
    # tools is now a list of CrewAI Tools matching 1:1 with the MCP server's tools
    agent = Agent(..., tools=tools)
    task = Task(...)
    crew = Crew(..., agents=[agent], tasks=[task])
    crew.kickoff(...)

# ** important ** don't forget to stop the connection
finally: 
    mcp_server_adapter.stop()

And finally the same thing but for an SSE MCP Server:

from mcp import StdioServerParameters
from crewai_tools import MCPServerAdapter

serverparams = {"url": "http://localhost:8000/sse"}

try:
    mcp_server_adapter = MCPServerAdapter(serverparams)
    tools = mcp_server_adapter.tools
    # tools is now a list of CrewAI Tools matching 1:1 with the MCP server's tools
    agent = Agent(..., tools=tools)
    task = Task(...)
    crew = Crew(..., agents=[agent], tasks=[task])
    crew.kickoff(...)

# ** important ** don't forget to stop the connection
finally: 
    mcp_server_adapter.stop()

Considerations & Limitations

Staying Safe with MCP

Always make sure that you trust the MCP Server before using it. Using an STDIO server will execute code on your machine. Using SSE is still not a silver bullet with many injection possible into your application from a malicious MCP server.

Limitations

  • At this time we only support tools from MCP Server not other type of primitives like prompts, resources...
  • We only return the first text output returned by the MCP Server tool using .content[0].text

Why Use CrewAI Tools?

  • Simplicity & Flexibility: Easy-to-use yet powerful enough for complex workflows.
  • Rapid Integration: Seamlessly incorporate external services, APIs, and databases.
  • Enterprise Ready: Built for stability, performance, and consistent results.

Contribution Guidelines

We welcome contributions from the community!

  1. Fork and clone the repository.
  2. Create a new branch (git checkout -b feature/my-feature).
  3. Commit your changes (git commit -m 'Add my feature').
  4. Push your branch (git push origin feature/my-feature).
  5. Open a pull request.

Developer Quickstart

pip install crewai[tools]

Development Setup

  • Install dependencies: uv sync
  • Run tests: uv run pytest
  • Run static type checking: uv run pyright
  • Set up pre-commit hooks: pre-commit install

Support and Community

Join our rapidly growing community and receive real-time support:

Build smarter, faster, and more powerful AI solutions—powered by CrewAI Tools.