Cron & Tasks¶

Prerequisites

This guide assumes you've completed the Quick Start and have a working summon config check.

summon-claude gives Claude two tools for managing ongoing work: cron jobs for time-based recurring actions, and tasks for tracking discrete units of work. Both are session-scoped and integrate with the canvas for visibility.

How you use cron and tasks¶

You don't need to know the tool names or parameters — just tell Claude what you want in your Slack session, and it handles the rest.

Scheduling recurring work:

"Check for new GitHub issues every hour and post a summary"

Claude creates a cron job that fires every hour with a prompt to check GitHub and summarize new issues. You see the results in your Slack channel each time the job runs.

Setting one-shot reminders:

"Remind me to review the PR at 3pm"

Claude creates a one-shot cron job scheduled for 3pm. When it fires, Claude posts a reminder in your channel. The job deletes itself after running once.

Tracking work items:

"Create a task to review the auth module — high priority"

Claude creates a task entry that appears on the session canvas. You can ask about task status anytime, and Claude updates tasks as work progresses.

Under the hood, Claude translates your requests into MCP tool calls (CronCreate, TaskCreate, etc.). The sections below document these tools for reference — but in practice, you just ask Claude in plain language.

Conversational examples¶

Here are examples of what you might type in Slack and what happens:

Setting up a recurring check:

"Set up a recurring check every 30 minutes for any failing CI jobs"

Claude creates a cron job with a 30-minute interval. Every 30 minutes, Claude checks CI status and posts in your channel only if there are failures. The job shows up on the canvas under Scheduled Jobs with its next run time.

Creating and querying tasks:

"Create a task to review the auth module — high priority"

Claude creates a high-priority task and confirms it. Later, you can ask:

"What tasks are open right now?"

Claude lists all pending and in-progress tasks for the session, showing their priority and current status.

Canceling a scheduled job:

"Stop checking for CI failures, I fixed the pipeline"

Claude finds the relevant cron job and cancels it. The job disappears from the canvas.

Cron jobs¶

How cron works¶

Each session has a SessionScheduler — a per-session asyncio scheduler that uses standard cron expressions to trigger Claude prompts on a schedule. When a job fires, the scheduler injects a message into the session as if a human sent it. Claude then processes the message and responds in Slack.

Cron jobs are agent-facing: Claude creates and manages them through MCP tools. They are not available from the terminal or Slack commands.

SDK session limitation

Cron tools (CronCreate, CronDelete, CronList) are only available in regular summon-claude sessions, not in SDK-spawned child sessions. Child sessions spawned by the PM should use TaskCreate/TaskUpdate for work tracking instead.

`CronCreate`¶

Create a scheduled job:

CronCreate(
  expression="0 9 * * 1-5",
  prompt="Check for new GitHub issues labeled 'needs-triage' and post a summary",
  recurring=true
)

Parameters:

Parameter	Description	Limit
`expression`	Cron expression (5-field format)	Minimum 60-second interval
`prompt`	Message sent to Claude when the job fires	1,000 characters max
`recurring`	If `true`, repeats on schedule. If `false`, runs once then deletes itself.	—

Limits:

Maximum 10 agent-created cron jobs per session
Minimum interval: 60 seconds (expressions resolving to sub-minute intervals are rejected)
Jobs expire after 24 hours regardless of the expression — create a new job if you need longer schedules
System jobs (created by summon-claude internally) cannot be created or deleted through MCP tools

`CronDelete`¶

Cancel a job by its ID:

CronDelete(job_id="cron-a1b2c3")

Cannot delete system jobs

Jobs with system=true are created by summon-claude for internal housekeeping. CronDelete rejects attempts to cancel them.

`CronList`¶

List all jobs for the current session:

CronList()

Returns a markdown table showing:

Column	Description
ID	Job identifier
Expression	Cron expression
Next run	Next scheduled fire time
Recurring	Yes / No (one-shot)
System	Whether the job is an internal summon job
Prompt	Truncated prompt text

Cron expression reference¶

summon-claude uses 5-field cron expressions (no seconds field):

┌─── minute (0-59)
│ ┌─── hour (0-23)
│ │ ┌─── day of month (1-31)
│ │ │ ┌─── month (1-12)
│ │ │ │ ┌─── day of week (0-7, where 0 and 7 are Sunday)
│ │ │ │ │
* * * * *

Common patterns:

Expression	Meaning
`/5 * * *`	Every 5 minutes
`0 * * * *`	Every hour, on the hour
`0 9 * * 1-5`	9:00 AM on weekdays
`0 9,17 * * *`	9:00 AM and 5:00 PM daily
`0 0 * * 0`	Midnight every Sunday
`30 8 1 * *`	8:30 AM on the 1st of each month

Tasks¶

Tasks are structured units of work tracked per session. Claude can create, update, and query tasks through MCP tools. The PM agent can query tasks across multiple child sessions to get a unified view of project progress.

`TaskCreate`¶

Create a new task:

TaskCreate(
  content="Review the authentication module for security issues",
  priority="high"
)

Parameters:

Parameter	Values	Description
`content`	Any text	Task description
`priority`	`high`, `medium`, `low`	Task priority (default: `medium`)

Limit: 100 tasks per session maximum.

`TaskUpdate`¶

Update an existing task:

TaskUpdate(
  task_id="task-a1b2c3",
  status="in_progress",
  content="Reviewing auth module — found JWT expiry issue",
  priority="high"
)

Parameters:

Parameter	Values	Description
`task_id`	Task ID	Required
`status`	`pending`, `in_progress`, `completed`	Update task status
`content`	Any text	Update task description
`priority`	`high`, `medium`, `low`	Update priority

All update fields are optional — only include what you want to change.

`TaskList`¶

List tasks for the current session:

TaskList()
# All tasks for this session

TaskList(status="in_progress")
# Filter by status

TaskList(session_ids=["sess-a1b2c3", "sess-d4e5f6"])
# PM cross-session query (PM only, max 20 sessions)

Parameters:

Parameter	Description
`status`	Optional filter: `pending`, `in_progress`, `completed`
`session_ids`	List of session IDs to query (PM only, up to 20 sessions)

The cross-session session_ids parameter is only available to PM agents. Regular sessions can only list their own tasks.

Canvas integration¶

Cron jobs and tasks both sync to the session canvas:

Cron jobs appear in a Scheduled Jobs section showing active jobs and their next run times
Tasks appear in a Tasks section grouped by status

The canvas updates automatically when jobs fire or tasks change status, so the PM (or you) can check the canvas for a snapshot of what each session is doing without asking Claude directly.

Example: PM-coordinated task workflow¶

Here is how a PM agent might use tasks to coordinate work across child sessions:

PM spawns worker-1 to handle authentication review
PM calls session_message to tell worker-1 to create a task for the review
worker-1 calls TaskCreate(content="Auth review", priority="high")
PM periodically calls TaskList(session_ids=["sess-worker-1"]) to check progress
PM updates the canvas Active Work table via summon_canvas_update_section

This gives you full visibility into the work distribution from the PM's Slack channel.

Cron & Tasks¶

How you use cron and tasks¶

Conversational examples¶

Cron jobs¶

How cron works¶

CronCreate¶

CronDelete¶

CronList¶

Cron expression reference¶

Tasks¶

TaskCreate¶

TaskUpdate¶

TaskList¶

Canvas integration¶

Example: PM-coordinated task workflow¶

See also¶

`CronCreate`¶

`CronDelete`¶

`CronList`¶

`TaskCreate`¶

`TaskUpdate`¶

`TaskList`¶