chore: enhance typing and documentation in tasks module (#3467)

- Disable E501 line length linting rule
- Add Google-style docstrings to tasks leaf file
- Modernize typing and docs in task_output.py
- Improve typing and documentation in conditional_task.py

pyproject.toml

@@ -131,6 +131,7 @@ select = [
     "I001",   # sort imports
     "I002",   # remove unused imports
 ]
+ignore = ["E501"]  # ignore line too long
 
 [tool.mypy]
 exclude = ["src/crewai/cli/templates", "tests"]

src/crewai/tasks/conditional_task.py

@@ -1,4 +1,7 @@
-from typing import Any, Callable
+"""Conditional task execution based on previous task output."""
+
+from collections.abc import Callable
+from typing import Any
 
 from pydantic import Field
 
@@ -8,37 +11,54 @@ from crewai.tasks.task_output import TaskOutput
 
 
 class ConditionalTask(Task):
-    """
-    A task that can be conditionally executed based on the output of another task.
-    Note: This cannot be the only task you have in your crew and cannot be the first since its needs context from the previous task.
+    """A task that can be conditionally executed based on the output of another task.
+
+    This task type allows for dynamic workflow execution based on the results of
+    previous tasks in the crew execution chain.
+
+    Attributes:
+        condition: Function that evaluates previous task output to determine execution.
+
+    Notes:
+        - Cannot be the only task in your crew
+        - Cannot be the first task since it needs context from the previous task
     """
 
-    condition: Callable[[TaskOutput], bool] = Field(
+    condition: Callable[[TaskOutput], bool] | None = Field(
         default=None,
-        description="Maximum number of retries for an agent to execute a task when an error occurs.",
+        description="Function that determines whether the task should be executed based on previous task output.",
     )
 
     def __init__(
         self,
-        condition: Callable[[Any], bool],
+        condition: Callable[[Any], bool] | None = None,
         **kwargs,
     ):
         super().__init__(**kwargs)
         self.condition = condition
 
     def should_execute(self, context: TaskOutput) -> bool:
-        """
-        Determines whether the conditional task should be executed based on the provided context.
+        """Determines whether the conditional task should be executed based on the provided context.
 
         Args:
-            context (Any): The context or output from the previous task that will be evaluated by the condition.
+            context: The output from the previous task that will be evaluated by the condition.
 
         Returns:
-            bool: True if the task should be executed, False otherwise.
+            True if the task should be executed, False otherwise.
+
+        Raises:
+            ValueError: If no condition function is set.
         """
+        if self.condition is None:
+            raise ValueError("No condition function set for conditional task")
         return self.condition(context)
 
-    def get_skipped_task_output(self):
+    def get_skipped_task_output(self) -> TaskOutput:
+        """Generate a TaskOutput for when the conditional task is skipped.
+
+        Returns:
+            Empty TaskOutput with RAW format indicating the task was skipped.
+        """
         return TaskOutput(
             description=self.description,
             raw="",

src/crewai/tasks/output_format.py

@@ -1,8 +1,16 @@
+"""Task output format definitions for CrewAI."""
+
 from enum import Enum
 
 
 class OutputFormat(str, Enum):
-    """Enum that represents the output format of a task."""
+    """Enum that represents the output format of a task.
+
+    Attributes:
+        JSON: Output as JSON dictionary format
+        PYDANTIC: Output as Pydantic model instance
+        RAW: Output as raw unprocessed string
+    """
 
     JSON = "json"
     PYDANTIC = "pydantic"

src/crewai/tasks/task_output.py

@@ -1,5 +1,7 @@
+"""Task output representation and formatting."""
+
 import json
-from typing import Any, Dict, Optional
+from typing import Any
 
 from pydantic import BaseModel, Field, model_validator
 
@@ -7,19 +9,31 @@ from crewai.tasks.output_format import OutputFormat
 
 
 class TaskOutput(BaseModel):
-    """Class that represents the result of a task."""
+    """Class that represents the result of a task.
+
+    Attributes:
+        description: Description of the task
+        name: Optional name of the task
+        expected_output: Expected output of the task
+        summary: Summary of the task (auto-generated from description)
+        raw: Raw output of the task
+        pydantic: Pydantic model output of the task
+        json_dict: JSON dictionary output of the task
+        agent: Agent that executed the task
+        output_format: Output format of the task (JSON, PYDANTIC, or RAW)
+    """
 
     description: str = Field(description="Description of the task")
-    name: Optional[str] = Field(description="Name of the task", default=None)
-    expected_output: Optional[str] = Field(
+    name: str | None = Field(description="Name of the task", default=None)
+    expected_output: str | None = Field(
         description="Expected output of the task", default=None
     )
-    summary: Optional[str] = Field(description="Summary of the task", default=None)
+    summary: str | None = Field(description="Summary of the task", default=None)
     raw: str = Field(description="Raw output of the task", default="")
-    pydantic: Optional[BaseModel] = Field(
+    pydantic: BaseModel | None = Field(
         description="Pydantic output of task", default=None
     )
-    json_dict: Optional[Dict[str, Any]] = Field(
+    json_dict: dict[str, Any] | None = Field(
         description="JSON dictionary of task", default=None
     )
     agent: str = Field(description="Agent that executed the task")
@@ -29,13 +43,28 @@ class TaskOutput(BaseModel):
 
     @model_validator(mode="after")
     def set_summary(self):
-        """Set the summary field based on the description."""
+        """Set the summary field based on the description.
+
+        Returns:
+            Self with updated summary field.
+        """
         excerpt = " ".join(self.description.split(" ")[:10])
         self.summary = f"{excerpt}..."
         return self
 
     @property
-    def json(self) -> Optional[str]:
+    def json(self) -> str | None:  # type: ignore[override]
+        """Get the JSON string representation of the task output.
+
+        Returns:
+            JSON string representation of the task output.
+
+        Raises:
+            ValueError: If output format is not JSON.
+
+        Notes:
+            TODO: Refactor to use model_dump_json() to avoid BaseModel method conflict
+        """
         if self.output_format != OutputFormat.JSON:
             raise ValueError(
                 """
@@ -47,8 +76,13 @@ class TaskOutput(BaseModel):
 
         return json.dumps(self.json_dict)
 
-    def to_dict(self) -> Dict[str, Any]:
-        """Convert json_output and pydantic_output to a dictionary."""
+    def to_dict(self) -> dict[str, Any]:
+        """Convert json_output and pydantic_output to a dictionary.
+
+        Returns:
+            Dictionary representation of the task output. Prioritizes json_dict
+            over pydantic model dump if both are available.
+        """
         output_dict = {}
         if self.json_dict:
             output_dict.update(self.json_dict)