CrewAI
Integrate CrewAI's role-based agent framework with Agent Kernel.
Installation
pip install agentkernel[crewai]
Basic Usage
from crewai import Agent as CrewAgent
from agentkernel.cli import CLI
from agentkernel.crewai import CrewAIModule
agent = CrewAgent(
role="assistant",
goal="Help users with their questions",
backstory="You are a helpful AI assistant",
verbose=False,
)
CrewAIModule([agent])
if __name__ == "__main__":
CLI.main()
Multi-Agent Crew
from crewai import Agent as CrewAgent, Task, Crew
from agentkernel.crewai import CrewAIModule
researcher = CrewAgent(
role="researcher",
goal="Research topics thoroughly",
backstory="You are an expert researcher",
verbose=False,
)
writer = CrewAgent(
role="writer",
goal="Write clear content",
backstory="You are a skilled writer",
verbose=False,
)
CrewAIModule([researcher, writer])
Configuration
export OPENAI_API_KEY=sk-... # CrewAI uses OpenAI by default
Tool Binding
Use CrewAIToolBuilder to bind plain Python functions as tools to your CrewAI agents:
from crewai import Agent as CrewAgent
from agentkernel.crewai import CrewAIModule, CrewAIToolBuilder
def get_weather(city: str) -> str:
"""Returns the weather for a given city."""
return f"Weather in {city}: sunny, 25°C"
agent = CrewAgent(
role="weather",
goal="You provide weather information",
backstory="Use the get_weather tool for weather-related questions.",
tools=CrewAIToolBuilder.bind([get_weather]),
)
CrewAIModule([agent])
See Tools for the full guide on writing and binding tools.
Structured Output
CrewAI configures structured output on the Task (output_pydantic / output_json), not on the agent, and Agent Kernel builds the task internally per run. Pass the model class to the module constructor, keyed by agent role; the runner forwards it into the task it creates:
from crewai import Agent as CrewAgent
from pydantic import BaseModel
from agentkernel.crewai import CrewAIModule
class ResearchReport(BaseModel):
topic: str
score: int
agent = CrewAgent(
role="Researcher",
goal="Research topics and score their relevance",
backstory="You are a meticulous researcher",
verbose=False,
)
CrewAIModule([agent], output_pydantic={"Researcher": ResearchReport})
# or: CrewAIModule([agent], output_json={"Researcher": ResearchReport})
To change the schema after the module is loaded, set it on the wrapped agent instead: module.get_agent("Researcher").output_pydantic = ResearchReport.
With output_pydantic, the CrewOutput.pydantic result is converted via model_dump(); with output_json, CrewOutput.json_dict is used directly. Plain-text crews continue to return AgentReplyText from CrewOutput.raw. str(reply) on an AgentReplyAny returns the JSON-serialized content, so text-based consumers work unchanged. See Reply Types for how structured replies are surfaced, and Execution Hooks for how hooks receive them.
Structured output applies to non-streaming execution only. Agent Kernel's CrewAI adapter does not
implement Runner.stream() yet (CrewAI itself supports streaming).
Per-run context/state
CrewAI does not support per-run caller context/state. Its kickoff(inputs=...) are .format() template-interpolation variables, not a state object, so there is no safe slot for a caller dict. If the reserved framework_context session key is set to a non-empty value, the CrewAI runner logs a single warning and ignores it (no injection, no write-back); the stored key is left untouched. A tool that still needs the dict can reach it directly via ToolContext.get().session.
Native run options
The Crew(...) constructor's own arguments (step_callback, task_callback, max_rpm, planning,
...) are declared per agent with Module.run_options.
Agent Kernel builds one Crew per run and writes the keys it owns (agents, tasks, memory)
last; verbose=False is a default you may override. CrewAI agents are registered by role, so that
is what resolves the agent:
CrewAIModule([agent]).run_options(
agent,
step_callback=record_step,
max_rpm=30,
)
Reserved (raise ValueError at declaration): agents, tasks, memory. Task-level options stay on
the module constructor (output_pydantic, output_json).
Human in the loop
This adapter cannot pause, and reports it rather than pretending: its runner leaves
supports_pause at False, and resume() raises if called directly. A request that tries to resume
a run on this framework is refused by Runtime with a message naming the runner.
The framework's own human-in-the-loop facility does not intersect what Agent Kernel wraps — see Human in the Loop for the five adapters that do pause.
Features
- ✅ Role-based agents
- ✅ Task delegation
- ✅ Sequential execution
- ✅ Hierarchical teams
- ✅ Framework-agnostic tool binding
- ✅ Structured output (
output_pydantic/output_json→AgentReplyAny)
Example
See examples/cli/crewai for complete examples.
For per-agent native run options, see examples/cli/crewai-run-options (a Crew step_callback and max_rpm, with a deterministic Run stats: line on every reply).
