Choosing quiet hours for an email agent: when to hold sends
Quiet hours are a daily window when an email agent will not send on its own. Set them from when your team can review, in the mailbox timezone.
On this page(9 sections)
- What do quiet hours do for an email agent?
- When should you set quiet hours?
- How do you choose the start and end times?
- Which timezone does the window use?
- What happens if the settings are wrong?
- How do quiet hours work with the daily cap?
- What should you do with held replies each morning?
- A short checklist
- Bottom line
Quiet hours are a daily time window in which an email agent is not allowed to send a reply by itself. Anything it would have sent in that window waits for a person to approve it. Choose the window to match the hours when nobody on your team could notice and fix a wrong reply.
Quiet hours are optional, and they matter only once an agent is in Auto mode. In Koltrix, Auto is Beta and off by default for every agent, and Suggest, where the agent drafts and a person clicks send, remains the default. This post covers how to pick the window, how the clock is read, and what you will see when the window holds a message.
What do quiet hours do for an email agent?
Quiet hours hold the agent's own sends during a window you define, and everything else about the agent keeps working. The agent can still read mail, classify it and prepare a reply. Only the autonomous send is held.
A held reply shows up in the Action center as an ordinary item waiting for a person, with the reason quiet_hours. It is not dropped and it is not sent later by itself. A person approves, edits or ignores it, the same as any other held item. Pending approvals expire after 7 days, so a window that holds replies for a normal night is no problem, but a long weekend of unreviewed items is worth a look.
Quiet hours are one of several checks, not a replacement for them. Auto in Koltrix also needs high confidence (at least 0.85) and an answer grounded in the mailbox's own facts, recipients already in the conversation, a message the injection shield rates as no risk, a daily cap above zero, and a 10-minute hold on identical messages. Quiet hours add a time dimension to those rules.
When should you set quiet hours?
Set quiet hours when the cost of a wrong reply grows if nobody is awake to catch it. The test is simple: if the agent sent something odd at 3 a.m., how many hours would pass before a person read it?
| Situation | Quiet hours? | Reasoning |
|---|---|---|
| One-person team that sleeps at night | Yes, cover the night | A bad reply would sit unseen for hours |
| Support team in one timezone, no night shift | Yes, cover off hours | Replies can wait for the morning review |
| Team with coverage in several timezones | Often not | Someone is always around to catch a mistake |
| Agent only answers low-risk, templated questions | Optional | The harm from a wrong reply is small |
| Agent replies about money, access or legal matters | Yes, and consider staying in Suggest | A wrong reply costs more than a slow one |
Quiet hours also work as a softer way to roll out Auto. Starting with a window that leaves only business hours open means every autonomous reply goes out while someone is at their desk.
How do you choose the start and end times?
Start the window when your last reviewer stops looking at the Action center, and end it when the first one starts. Do not guess from the clock on the wall. Look at when held items actually get approved.
- Run the agent in Suggest or Approve for a week and note when a person normally approves replies. The first and last approval of each day are your edges.
- Set the start a little before the last approval and the end a little after the first. A buffer is cheap, because a held reply costs you a few minutes.
- Check the weekend separately. A window of 20:00 to 08:00 covers every night, but it does not cover a Saturday when nobody looks at the Action center at all.
- Write down the window and the person who reviews the morning backlog, so the first hour of the day is not a surprise.
A narrow window is not always better. Too wide and the agent holds so much that a person ends up approving everything by hand, which defeats the point of Auto. Too narrow and a wrong reply can slip out at 7:50 a.m. before anyone has opened their laptop.
Which timezone does the window use?
Quiet hours are read in the timezone you give for the agent mailbox, and that timezone is required whenever quiet hours are on. Use an IANA name such as Asia/Kolkata or America/New_York, not an abbreviation like IST or EST. The same timezone also decides when the daily send cap resets, at midnight in the mailbox's own timezone.
The window is a half-open range: the start minute is quiet and the end minute is not. A window that crosses midnight, such as 20:00 to 08:00, is handled as one overnight window. Setting the same start and end creates an empty window, so nothing is held. If you want no quiet hours, turn the setting off instead of relying on that.
| Setting | Quiet from | Quiet until | Sends allowed |
|---|---|---|---|
20:00 to 08:00, Asia/Kolkata |
8 p.m. India time | 8 a.m. India time | 8:00 a.m. to 7:59 p.m. |
22:00 to 06:30, America/New_York |
10 p.m. Eastern | 6:30 a.m. Eastern | 6:30 a.m. to 9:59 p.m. |
| 09:00 to 17:00 | 9 a.m. | 5 p.m. | Only outside working hours |
The last row is deliberate: a window does not have to be a night. A team that wants the agent to stay silent during working hours, when humans answer directly, can set the window over the working day instead.
What happens if the settings are wrong?
Koltrix treats a bad quiet-hours setting as a reason to hold, not to send. If the timezone cannot be read or a time is malformed, the check counts the moment as quiet, so a typo cannot widen what the agent sends alone. When you save the setting, the start and end must look like 20:00 and the timezone must be a valid IANA name, or the save is refused with an error.
This is the same principle as the rest of the guardrails: when a rule cannot be evaluated, the safe outcome is a held message. If an agent suddenly holds everything with the reason quiet_hours, check the timezone and the two times before anything else.
How do quiet hours work with the daily cap?
They answer different questions. The daily send cap limits how many replies an agent sends in a day. Quiet hours limit when it may send them. An agent can be under its cap and still be held by a quiet window, and it can be inside open hours and still be held because it hit the cap.
Used together they bound the damage of a bad day in two directions: a cap stops a flood, and a window stops a problem nobody is awake to see. For an agent that is also exposed to bot-to-bot replies, both help; see when two agents answer each other.
What should you do with held replies each morning?
Treat the Action center like an inbox with a fixed start time. Open it first, read what the window held, and approve the ones you would have sent. Our post on what an approval step should show lists what a reviewer needs to see to do that quickly.
Two patterns are worth acting on:
- Many
quiet_hoursitems you approve unchanged. The agent is doing good work and the window may be wider than it needs to be. Narrow it a little, or leave it if the review is quick. - Many
quiet_hoursitems you reject or heavily edit. The window is doing its job, but the real problem is the agent's scope or notes. Move it back to Suggest and fix the cause. For how to choose what an agent should handle, read least privilege for email agents.
A short checklist
- The agent has run in Suggest or Approve long enough that you know when people review.
- The window starts when the last reviewer stops and ends when the first starts.
- The mailbox timezone is an IANA name for where your reviewers are.
- Weekends and holidays are covered by a person, or you accept the backlog on Monday.
- Someone owns the morning pass over held items.
- You know where the kill switch is, because one switch puts every agent back to Suggest.
The window and the cap are both Auto settings on an agent mailbox; the agent mailboxes page describes the controls.
Bottom line
Quiet hours stop an email agent from sending on its own when no person could catch a mistake. Pick the window from the real hours your reviewers work, set it in the mailbox timezone with an IANA name, and let held replies wait in the Action center. Auto is Beta and Suggest remains the default, so start there, add a daily cap and quiet hours before switching Auto on, and review what the window holds until you trust it.
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