Creates and manages a structured task list for tracking progress on complex, multi-step coding tasks.

<when_to_use> Use this tool proactively in these scenarios:

• Complex multi-step tasks requiring 3+ distinct steps or actions
• Non-trivial tasks requiring careful planning or multiple operations
• User explicitly requests todo list management
• User provides multiple tasks (numbered or comma-separated list)
• After receiving new instructions to capture requirements
• When starting work on a task (mark as in_progress BEFORE beginning)
• After completing a task (mark completed and add new follow-up tasks) </when_to_use>

<when_not_to_use> Skip this tool when:

• Single, straightforward task
• Trivial task with no organizational benefit
• Task completable in less than 3 trivial steps
• Purely conversational or informational request </when_not_to_use>

<task_states>

• pending: Task not yet started
• in_progress: Currently working on (limit to ONE task at a time)
• completed: Task finished successfully

IMPORTANT: Each task requires two forms:

• content: Imperative form describing what needs to be done (e.g., "Run tests", "Build the project")
• active_form: Present continuous form shown during execution (e.g., "Running tests", "Building the project") </task_states>

<task_management>

• Update task status in real-time as you work
• Mark tasks complete IMMEDIATELY after finishing (don't batch completions)
• Exactly ONE task must be in_progress at any time (not less, not more)
• Complete current tasks before starting new ones
• Remove tasks that are no longer relevant from the list entirely </task_management>

<completion_requirements> ONLY mark a task as completed when you have FULLY accomplished it.

Never mark completed if:

• Tests are failing
• Implementation is partial
• You encountered unresolved errors
• You couldn't find necessary files or dependencies

If blocked:

• Keep task as in_progress
• Create new task describing what needs to be resolved </completion_requirements>

<task_breakdown>

• Create specific, actionable items
• Break complex tasks into smaller, manageable steps
• Use clear, descriptive task names
• Always provide both content and active_form </task_breakdown>

❌ Bad task (missing active_form):

{
  "content": "Fix bug",
  "status": "pending"
}

<output_behavior> NEVER print or list todos in your response text. The user sees the todo list in real-time in the UI. </output_behavior>