AgentTeam Task Validation

What AgentTeam accepts for tasks= and the exact errors you'll see

AgentTeam only accepts tasks=None (auto-generate one per agent) or a list / tuple of Task instances — anything else raises a clear TypeError at construct time.

Diagram

Quick Start

Let the team auto-generate tasks

python

from praisonaiagents import Agent, AgentTeam

writer = Agent(name="Writer", instructions="Write a short bio")
team = AgentTeam(agents=[writer])  # tasks=None by default
team.start("Write one sentence about rain")

tasks=None generates one task per agent — the shortest working run.

Pass explicit Task instances

python

from praisonaiagents import Agent, AgentTeam, Task

writer = Agent(name="Writer", instructions="Write a short bio")
task = Task(
    description="Write one sentence about rain",
    expected_output="One sentence",
    agent=writer,
)

team = AgentTeam(agents=[writer], tasks=[task])
team.start()

Use a list of Task instances when you need per-task control.

Common Mistake

tasks= is not a prompt string — passing one raises a TypeError.

python

# ❌ Wrong — tasks is not a prompt string
team = AgentTeam(agents=[writer], tasks="Write one sentence")
# TypeError: tasks must be a sequence of Task instances, not str.
# Pass tasks=None to auto-generate from agents, or tasks=[Task(...)].

Fix it by passing the prompt to start(), or wrapping it in a Task.

Option A — prompt goes to start()

from praisonaiagents import Agent, AgentTeam

writer = Agent(name="Writer", instructions="Write a short bio")
team = AgentTeam(agents=[writer])
team.start("Write one sentence")

Option B — wrap as Task

from praisonaiagents import Agent, AgentTeam, Task

writer = Agent(name="Writer", instructions="Write a short bio")
task = Task(
    description="Write one sentence",
    expected_output="One sentence",
    agent=writer,
)
team = AgentTeam(agents=[writer], tasks=[task])

Accepted and Rejected Inputs

Every tasks= value resolves to one of these outcomes.

`tasks=` value	Result
`None`	Auto-generates one task per agent
`[Task(...), Task(...)]`	Accepted
`(Task(...),)`	Accepted (tuple works)
`[]`	`ValueError("If tasks are provided, at least one task must be present")`
`"Write ..."`	`TypeError` naming `Task` and the valid shapes
`b"..."`	`TypeError`
`123`	`TypeError("tasks must be a sequence of Task instances, got int")`
`[task, "x"]`	`TypeError("tasks[1] must be a Task instance, got str")`

Error Reference

Grep these exact messages when you hit a failure.

Input	Exception	Message
`str` / `bytes`	`TypeError`	`tasks must be a sequence of Task instances, not str. Pass tasks=None to auto-generate from agents, or tasks=[Task(...)].`
Non-sequence (e.g. `int`)	`TypeError`	`tasks must be a sequence of Task instances, got int`
Sequence with a non-`Task` item	`TypeError`	`tasks[1] must be a Task instance, got str`
Empty list / tuple	`ValueError`	`If tasks are provided, at least one task must be present`

Best Practices

Prefer tasks=None for simple runs

Pass the prompt to start() and let the team auto-generate one task per agent — often all you need.

Use Task(…) when you need per-task control

Task(description=..., expected_output=..., agent=...) gives you templating with {{placeholder}}, custom expected_output, and a specific agent=.

A tuple of Task works too

tasks=(t1, t2) is accepted — the sequence is coerced to a list internally, useful when the task list is static.

Empty list is a ValueError, not a TypeError

tasks=[] has always raised ValueError — that check pre-dates the strict type validation.

AgentTeam

The team class and its full parameter list.

AgentTeam Params

Which params apply at the team level.

Batch Runs

Run the same team once per input.

Tasks

Task configuration and templating.