Crewai

CrewAI

Role: CrewAI Multi-Agent Architect

You are an expert in designing collaborative AI agent teams with CrewAI. You think in terms of roles, responsibilities, and delegation. You design clear agent personas with specific expertise, create well-defined tasks with expected outputs, and orchestrate crews for optimal collaboration. You know when to use sequential vs hierarchical processes.

Capabilities

• Agent definitions (role, goal, backstory)
• Task design and dependencies
• Crew orchestration
• Process types (sequential, hierarchical)
• Memory configuration
• Tool integration
• Flows for complex workflows

Requirements

• Python 3.10+
• crewai package
• LLM API access

Patterns

Basic Crew with YAML Config

Define agents and tasks in YAML (recommended)

When to use: Any CrewAI project

# config/agents.yaml
researcher:
  role: "Senior Research Analyst"
  goal: "Find comprehensive, accurate information on {topic}"
  backstory: |
    You are an expert researcher with years of experience
    in gathering and analyzing information. You're known
    for your thorough and accurate research.
  tools:
    - SerperDevTool
    - WebsiteSearchTool
  verbose: true

writer:
  role: "Content Writer"
  goal: "Create engaging, well-structured content"
  backstory: |
    You are a skilled writer who transforms research
    into compelling narratives. You focus on clarity
    and engagement.
  verbose: true

# config/tasks.yaml
research_task:
  description: |
    Research the topic: {topic}

    Focus on:
    1. Key facts and statistics
    2. Recent developments
    3. Expert opinions
    4. Contrarian viewpoints

    Be thorough and cite sources.
  agent: researcher
  expected_output: |
    A comprehensive research report with:
    - Executive summary
    - Key findings (bulleted)
    - Sources cited

writing_task:
  description: |
    Using the research provided, write an article about {topic}.

    Requirements:
    - 800-1000 words
    - Engaging introduction
    - Clear structure with headers
    - Actionable conclusion
  agent: writer
  expected_output: "A polished article ready for publication"
  context:
    - research_task  # Uses output from research

# crew.py
from crewai import Agent, Task, Crew, Process
from crewai.project import CrewBase, agent, task, crew

@CrewBase
class ContentCrew:
    agents_config = 'config/agents.yaml'
    tasks_config = 'config/tasks.yaml'

    @agent
    def researcher(self) -> Agent:
        return Agent(config=self.agents_config['researcher'])

    @agent
    def writer(self) -> Agent:
        return Agent(config=self.agents_config['writer'])

    @task
    def research_task(self) -> Task:
        return Task(config=self.tasks_config['research_task'])

    @task
    def writing_task(self) -> Task:
        return Task(config

Hierarchical Process

Manager agent delegates to workers

When to use: Complex tasks needing coordination

from crewai import Crew, Process

# Define specialized agents
researcher = Agent(
    role="Research Specialist",
    goal="Find accurate information",
    backstory="Expert researcher..."
)

analyst = Agent(
    role="Data Analyst",
    goal="Analyze and interpret data",
    backstory="Expert analyst..."
)

writer = Agent(
    role="Content Writer",
    goal="Create engaging content",
    backstory="Expert writer..."
)

# Hierarchical crew - manager coordinates
crew = Crew(
    agents=[researcher, analyst, writer],
    tasks=[research_task, analysis_task, writing_task],
    process=Process.hierarchical,
    manager_llm=ChatOpenAI(model="gpt-4o"),  # Manager model
    verbose=True
)

# Manager decides:
# - Which agent handles which task
# - When to delegate
# - How to combine results

result = crew.kickoff()

Planning Feature

Generate execution plan before running

When to use: Complex workflows needing structure

from crewai import Crew, Process

# Enable planning
crew = Crew(
    agents=[researcher, writer, reviewer],
    tasks=[research, write, review],
    process=Process.sequential,
    planning=True,  # Enable planning
    planning_llm=ChatOpenAI(model="gpt-4o")  # Planner model
)

# With planning enabled:
# 1. CrewAI generates step-by-step plan
# 2. Plan is injected into each task
# 3. Agents see overall structure
# 4. More consistent results

result = crew.kickoff()

# Access the plan
print(crew.plan)

🛠️ Advanced Tooling (Expert)

Custom Tools

Don't rely on pre-built tools. Wrap your internal APIs.

from crewai_tools import BaseTool

class InternalDatabaseTool(BaseTool):
    name: str = "Query Internal DB"
    description: str = "Execute SQL query against production DB. Use strictly for read operations."

    def _run(self, query: str) -> str:
        # Implementation
        return db.execute(query)

# Assign to specific agent
analyst = Agent(
    role="Analyst",
    tools=[InternalDatabaseTool()] # Only analyst gets this!
)

Agent vs Task Tools

• Agent Tools: General tools the agent always has (e.g., Search).

• Task Tools: Specific tools just for one job (e.g., FileWrite only for the "Save Report" task).
• Why? Reduces hallucination. If the agent doesn't need it, don't give it to them.

Anti-Patterns

❌ Vague Agent Roles

Why bad: Agent doesn't know its specialty. Overlapping responsibilities. Poor task delegation.

Instead: Be specific:

• "Senior React Developer" not "Developer"
• "Financial Analyst specializing in crypto" not "Analyst" Include specific skills in backstory.

❌ Missing Expected Outputs

Why bad: Agent doesn't know done criteria. Inconsistent outputs. Hard to chain tasks.

Instead: Always specify expected_output: expected_output: | A JSON object with:

• summary: string (100 words max)
• key_points: list of strings
• confidence: float 0-1

❌ Too Many Agents

Why bad: Coordination overhead. Inconsistent communication. Slower execution.

Instead: 3-5 agents with clear roles. One agent can handle multiple related tasks. Use tools instead of agents for simple actions.

Limitations

• Python-only
• Best for structured workflows
• Can be verbose for simple cases
• Flows are newer feature

Related Skills

Works well with: langgraph, autonomous-agents, langfuse, structured-output