What a cron job is and what AI adds
A cron job is a task that runs automatically on a schedule. The name comes from cron, the time based job scheduler on Unix systems, which has run backups, cleanups and reports on servers for decades. A line in a file says "at this time, run this command", and the system does it without anyone logging in.
A classic cron job runs a fixed script. It does exactly what the code says and nothing more. If the website it scrapes changes layout, the script breaks. If the data has a new edge case, someone has to edit the code.
An AI cron job keeps the schedule but replaces the fixed script with an AI agent. Each time the schedule fires, the agent reads its sources, decides what matters, compares with what it saw last run and delivers a result. It can handle messy inputs such as web pages and documents, and it can explain its reasoning in a run log. In Crons each of these scheduled agents is called a cron, and the AI cron jobs feature page shows the full set of steps a cron can use.
The five fields of cron syntax
A standard cron expression has five fields separated by spaces. Each field narrows down when the job runs. Read them from left to right: minute, hour, day of month, month, day of week.
| Position | Field | Allowed values | Example value and meaning |
|---|---|---|---|
| 1 | Minute | 0 to 59 | 30 means at minute 30 |
| 2 | Hour | 0 to 23 | 8 means 8 AM, 14 means 2 PM |
| 3 | Day of month | 1 to 31 | 1 means the first day of the month |
| 4 | Month | 1 to 12 or JAN to DEC | 1,4,7,10 means January, April, July and October |
| 5 | Day of week | 0 to 6 or SUN to SAT (0 is Sunday) | MON-FRI means Monday through Friday |
Special characters you will see
- Asterisk means every value. An asterisk in the hour field means every hour.
- Comma lists values. 1,15 in the day of month field means the 1st and the 15th.
- Hyphen sets a range. 1-5 in the day of week field means Monday to Friday.
- Slash sets a step. */15 in the minute field means every 15 minutes.
When both day of month and day of week are restricted, most cron implementations run the job when either one matches, not both. This surprises many people, and it is one reason plain English schedules are easier to get right.
Cron expression examples for business jobs
The table below translates common business schedules into cron expressions. Times are in whatever timezone the job is set to, which we cover in the next sections.
| Cron expression | Plain English | Typical AI cron job |
|---|---|---|
| 0 8 * * 1 | Every Monday at 8 AM | Weekly competitor pricing check |
| 0 7 * * 1-5 | Every weekday at 7 AM | Morning lead list refresh |
| 30 17 * * 5 | Every Friday at 5:30 PM | Weekly customer health digest |
| 0 9 1 * * | On the 1st of every month at 9 AM | Monthly invoice reconciliation |
| 0 */4 * * * | Every 4 hours on the hour | Job board scan for a hard to fill role |
| */15 * * * * | Every 15 minutes | Status page or inventory watch (Pro and Teams) |
| 0 6 * * 1,4 | Every Monday and Thursday at 6 AM | Twice weekly SEO audit of key pages |
Several of these match ready made Crons templates, such as the invoice reconciliation template for the monthly job and the lead generation template for the weekday refresh.
Plain English schedules versus cron expressions
Cron syntax is compact and precise, but it is easy to misread. "0 8 * * 1" and "0 1 * * 8" look similar and mean very different things, and the second one is not even valid in most systems. For business teams the expression is an implementation detail. What matters is the sentence a person would say.
In Crons you write the schedule as part of the job: "every weekday at 7 AM Chicago time", "on the first business day of each month", "every Monday and Thursday at 6 AM". Crons parses that into a cron expression plus a timezone and shows you both, along with the next few run times, before you save. If the parse is not what you meant, you rephrase the sentence instead of debugging asterisks.
| Aspect | Plain English in Crons | Raw cron expression |
|---|---|---|
| Who can write it | Anyone on the team | Someone who knows the syntax |
| Timezone | Stated in the sentence and shown | Depends on the server, often UTC |
| Review | Next run times shown before saving | Read by eye or with a separate tool |
| Edits | Change the sentence | Edit fields and recheck |
You can read more about how the parsing works on the natural language schedules page.
Timezones and daylight saving time
A cron expression on its own has no timezone. Traditional servers usually run in UTC, so "0 8 * * 1" fires at 8 AM UTC, which is 3 AM or 4 AM in New York depending on the season. Many missed reports trace back to this.
Every cron in Crons stores an explicit timezone alongside the expression. When you write "8 AM London time", the job runs at 8 AM in London all year, and the schedule follows daylight saving changes automatically. Reports keep landing at the same local time your team expects.
The two edge cases around clock changes
- Spring forward. When clocks jump ahead, a local time such as 2:30 AM does not exist that night. Avoid scheduling business jobs in the hour of the change, typically between 1 AM and 3 AM local time.
- Fall back. When clocks go back, a local time such as 1:30 AM happens twice. Again, picking a time outside the change window avoids any ambiguity.
For distributed teams, set each cron to the timezone of the people who read the result, not the timezone of whoever built it. A digest for a sales team in Sydney should run on Sydney time.
Minimum frequency and usage on each plan
Every AI cron job uses resources on each run: one run, some AI calls and, for browser actions, browser minutes. That is why the shortest interval depends on your plan.
| Plan | Minimum frequency | Runs per month | Active crons |
|---|---|---|---|
| Starter | Every 1 hour | 300 | 10 |
| Pro | Every 15 minutes | 1,500 | 50 |
| Teams | Every 5 minutes | 6,000 | Unlimited, fair use |
A quick rule of thumb helps with planning. A weekly cron uses about 4 or 5 runs a month, a weekday cron about 22, a daily cron about 30 and an hourly cron about 720. On Starter, ten weekly and daily crons fit comfortably in 300 runs, while one hourly cron alone would exceed it. Crons alerts you at 80 percent of a limit and stops before the limit is passed. Usage is counted per billing period, and deleting a cron never returns usage. See Crons pricing for AI calls and browser minutes per plan.
Choosing the right schedule for an AI cron job
The right schedule is the slowest one that still delivers the information in time to act on it. Ask three questions.
- 1How often does the source actually change? Pricing pages change monthly at most, job boards daily, status pages minute by minute.
- 2When will someone act on the result? A Monday morning report only needs to arrive before the Monday meeting.
- 3What does a run cost in AI calls and browser minutes? Faster schedules multiply that cost.
Memory makes slower schedules more useful, not less. Because each run compares with the last one and reports only what changed, a weekly cron never misses a price change. It just reports it once, on the next run, with the before and after values.
Common mistakes with AI cron jobs
Most problems with scheduled AI jobs come from a short list of avoidable choices. Checking for them before you save a cron saves hours of confusion later.
- Forgetting the timezone. A report that should land at 8 AM for the team arrives in the middle of the night because the schedule was read as UTC. Always state the city or timezone in the sentence.
- Scheduling faster than the source changes. Checking a monthly pricing page every hour burns runs and AI calls and produces nothing new on almost every run.
- Skipping memory. Without a stored baseline, every run reports everything it sees, and readers stop paying attention.
- Ignoring the day of month and day of week rule. Restricting both fields in a raw expression usually means "either", not "both", which can double the number of runs.
- Stacking many crons at the same minute. Ten jobs all set for exactly 9:00 AM finish later than the same jobs spread across the hour. Small offsets such as 9:05 and 9:10 keep results arriving steadily.
- No failure alert. A job that silently fails for three weeks is worse than no job. Turn on alerts by email or Slack for every cron that someone depends on.
A good habit is to read the run log of a new cron after its first two scheduled runs. The log shows each step, its input and output, any retries and how long it took, so you can confirm that the schedule, the sources and the memory behave the way the sentence intended.
Examples of AI cron jobs by team
The same scheduling ideas apply across departments. Here are typical AI cron jobs teams set up first, each written the way you would type it into Crons.
- Sales. "Every weekday at 7 AM find new companies that match our ideal customer profile and add them to HubSpot, skipping any we already have."
- Marketing. "Every Monday at 6 AM audit our top 30 pages for broken links, missing titles and slow responses and post a summary to Slack."
- Recruiting. "Every morning at 8 AM search for senior backend engineers in Berlin and send me only profiles I have not seen before."
- Finance. "On the first of each month at 9 AM match last month's invoices with payments in our sheet and list anything unmatched."
- Customer success. "Every Friday at 4 PM summarize accounts with falling usage and draft a check in email for approval."
Each of these becomes a cron expression, a timezone, a set of steps and a delivery target. Browse more starting points by department on the Crons use cases page.
Frequently asked questions
What is an AI cron job?
An AI cron job is a scheduled task where an AI agent does the work each time the schedule fires. It reads sources, reasons about them, remembers past results and delivers what changed, instead of running a fixed script.
Do I need to know cron syntax to use Crons?
No. You write the schedule in plain English, such as "every weekday at 7 AM Chicago time", and Crons converts it into a cron expression with a timezone. You see the expression and the next run times before you save.
What does */15 mean in a cron expression?
In the minute field, */15 means every 15 minutes, so the job runs at minutes 0, 15, 30 and 45 of every matching hour. On Crons that frequency is available on Pro and Teams.
How does Crons handle daylight saving time?
Each cron stores an explicit timezone, so a job set for 8 AM London time runs at 8 AM local time all year and follows clock changes automatically. Avoid scheduling inside the hour when clocks change.
How are AI cron jobs different from cron monitoring?
An AI cron job does the work itself. A cron monitor only watches jobs that run elsewhere and alerts when they are late or fail. Read AI cron jobs vs cron monitoring for a full comparison.