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Wait Tool

docs/edge/en/tools/automation/waittool.mdx

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Overview

The WaitTool pauses execution for a given number of seconds. It exists because agents that kick off long-running work — a sandbox build, a deployment, a batch import, an async API job — otherwise have no way to let time pass. Without it, an agent either polls in a tight loop or gives up before the work finishes.

The tool takes no API key and has no dependencies beyond the standard library.

When to Use It

The tool's description tells the model to reach for it when out-of-band work needs real time to progress:

  • A sandbox build, test run, or script that is still executing
  • A deployment or provisioning step that is still rolling out
  • A batch import, export, or training job
  • An async API that returned a job id to poll later
  • A rate limit or backoff that has to cool down before retrying

The pattern the model is steered toward is: start the job, wait, check status, wait again if it is still running. The description also tells it not to wait to pace a conversation or when the information it needs is already available — waiting only lets clock time pass, it does not advance or check the job.

Installation

The tool ships with crewai-tools:

shell
uv add crewai-tools

Example

python
from crewai import Agent, Crew, Task
from crewai.tools import tool
from crewai_tools import WaitTool

wait_tool = WaitTool()


@tool("Check build status")
def check_build_status_tool(build_id: str) -> str:
    """Return the current status of a build: queued, running, passed, or failed."""
    # Replace this with a call to your own build system.
    return my_ci_client.get_build(build_id).status


build_agent = Agent(
    role="Build Monitor",
    goal="Start the build and report its final status",
    backstory="An engineer who knows that builds take time.",
    tools=[wait_tool, check_build_status_tool],
    verbose=True,
)

monitor_task = Task(
    description=(
        "Start the build, then wait and re-check its status until it finishes."
    ),
    expected_output="The final build status.",
    agent=build_agent,
)

crew = Crew(agents=[build_agent], tasks=[monitor_task])
result = crew.kickoff()

Arguments

ArgumentTypeRequiredDescription
secondsfloatHow many seconds to wait. Must be zero or greater.
reasonstrOptional note on what is being waited for. Echoed back in the tool's result.

Initialization Parameters

ParameterTypeDefaultDescription
max_secondsfloat300Upper bound for a single wait. Longer requests are capped to this value, not rejected.

Capping Long Waits

A single call waits at most max_seconds. If an agent asks for more, the tool waits the maximum and says so in its result, so the agent can call it again rather than fail:

python
wait_tool = WaitTool()
wait_tool.run(seconds=3600)
# 'Waited 300 seconds. Requested 3600 seconds, capped at 300 seconds per call -
#  call this tool again if more waiting is needed.'

Raise the cap when a workflow genuinely needs longer single pauses:

python
wait_tool = WaitTool(max_seconds=1800)

Async Support

The tool implements both sync and async execution, so it does not block the event loop when awaited:

python
import asyncio


async def main():
    result = await wait_tool.arun(seconds=30, reason="waiting for the sandbox build")
    print(result)


asyncio.run(main())