Settings

Settings

This page covers every option in Preen's settings. The settings page has 15 sections. This page has one part for each.

Each option on this page has three lines:

• What it does.
• Change it when.
• Default. This is what you get if you never touch it.

Words you will see:

• Jev is the AI model that Preen asks about your mail.
• Certainty is how sure Jev must be before Preen adds a tag. It goes from 0 to 1. A higher number means fewer tags and fewer mistakes. A lower number means more tags and more mistakes.
• Low, Medium, High and Custom are buttons beside many numbers. Each of Low, Medium and High sets a number for you. Custom lets you type your own.
• Rows. Each setting is one row. Its name and control are on the left and its description is on the right. On a narrow window the description moves under the control.

Getting around

• The list on the left shows the sections. Click one to bring it to the top.
• Modes. The first time you open Settings, a card asks how much you want to set up. Simple shows View, Provider & cost, Getting started, and the mailboxes for automatic processing. Standard adds the schedule, limits and categories. Everything shows all 15 sections. The switch for the mode is in the first section, View. Click Simple, Standard or Everything to change it at once. The three buttons show one, two or three feathers. Preen remembers your choice. Find a setting still finds options in hidden sections and switches to the mode that shows them.
• View is the first section. Provider & cost is next, because Preen does nothing until a provider and key are set.
• Find a setting is a search box. Press Ctrl+K to jump to it.
• The top bar, from the left after the title: two chips, the Activity log button and Save.
  • The chips show if the last connection test worked ("Not tested" until it does) and if automatic processing is on ("Automatic off" when it is not).
  • Activity log is an icon button that opens the activity page. The left menu has the same link, named Activity.
  • Save saves your changes.
• Each section has an icon in its header. Click it to read a short note about that section.
• Small "More about" buttons open short tips.

When you change something, an Unsaved changes tray appears. It lists each change with the old and new value. Use Discard to throw the changes away or Save to keep them. If you change a setting back by hand, it drops off the list; once every value is back as saved, the tray closes and the Save button loses its dot.

Two kinds of controls look different:

• Some controls save at once, like your agreement to send mail and debug mode. A small check mark and "Saved" flash next to them.
• Others wait for Save. They show a dot and "Not saved yet" until you click Save or Discard. Apply on a correction suggestion works this way.

1. View

Setting

Details

Settings shown (Simple, Standard, Everything)

What it does: sets how much of the settings page you see. Simple has the essentials. Standard has what most people use. Everything has every setting, including advanced and debug. Settings you hide keep their values and still work. Preen remembers your choice on this computer. Change it when: you want fewer or more settings in view. Default: you choose the first time you open Settings. Until you choose, Standard is shown.

2. Provider & cost

Setting	Details
Provider	What it does: picks who receives your mail data. The choices are OpenRouter and TypeSafe. Change it when: your API key is from the other one. Default: OpenRouter.
Model (optional)	What it does: names the model to use. If you leave it empty, Preen uses the provider's default model. That is jev-1.13 on OpenRouter and jev-1.13.0 on TypeSafe. Change it when: you want a different model name. Most people leave it empty. Default: empty.
API key	What it does: this is your key for the provider. Preen sends it only to that provider. It is stored without encryption in your Thunderbird profile. You can find out what a key is and how to get one in Getting an API key. Change it when: you first set up Preen, or you get a new key. Use a key made just for Preen, with a credit limit. Default: empty.
Test connection	What it does: sends one tiny yes/no question to check your key, the model and the connection. It sends no mail, and a note beside the button says so. Thunderbird may first ask for permission to contact the provider. When it works, Preen shows the model name and the tokens used. Change it when: you add or change a key, or something stops working. Default: not applicable. It is a button. The chip at the top says "Not tested" until a test works.
I agree, allow sending	What it does: this is your OK to send mail data to the provider you picked. Until you click it, Preen sends no mail. Your OK is for one provider. Above the button is a short summary of what is sent. Everything that is sent, and why opens the full list, with a short reason for each item. A choice, How much of each message to send, sets Surface or Deep. It is the same setting as Default depth under Accounts. Change it when: you have read the note and you agree. Default: no OK given.
Not now	What it does: closes the question and keeps sending turned off. Change it when: you are not ready to agree. Default: not applicable. It is a button.
Privacy policy	What it does: a link in the consent card. It opens the full privacy policy in a tab inside Preen. It works offline. Change it when: you want to read what Preen does with your data. Default: not applicable. It is a link.
Withdraw consent	What it does: takes your OK back at any time. Preen stops sending. Change it when: you change your mind. Default: not applicable. It is a button.
Price per million input tokens (USD)	What it does: lets Preen turn tokens into dollars. A token is a small piece of text that the model reads. Preen counts tokens but has no price built in. With a price, Preen shows a line such as "about $X per 100 emails and $Y per 1,000 emails". These are estimates from your past use. Before you have sorted any mail, the line says "at least about". Change it when: you want to see costs in dollars, or you want a monthly cost limit. Test connection fills this in if your provider reports a cost. Default: empty. Preen shows tokens only.
Estimated monthly cost limit (USD, optional)	What it does: Preen stops running when this month's estimate reaches the limit. The estimate is this month's tokens times your price. So it needs a price. Until there is one, the box is locked, and a note says to type a price or click Test connection. Once Preen can work it out, a Use $N button offers a starting limit. It fills the box only. Nothing is saved until you click Save. Change it when: you want a spending cap inside Preen. Also set a credit limit on your key at your provider. That is the hard stop. Default: empty. No limit.

3. Getting started

Setting	Details
The Getting started line	What it does: Getting started is one line. It shows the next step to do, or "Setup complete" when all four steps are done, and how many steps are done. Click it ("Show steps") to see the four steps, with a short demo of the right-click step beside them. Change it when: you want to read the steps again. Default: closed.
Try it on the last 7 days	What it does: runs a preview of the last 7 days of mail in the mailboxes you ticked under Automatic processing. A dialog first shows how many messages will be sent and an estimate of the cost. Nothing in your mail changes. When it is done, the review opens on the Activity page, where you can apply what looks right. Change it when: you want to see Preen's results on real recent mail before you set Preen to run on its own. Default: not applicable. It is a button. It needs a ticked mailbox and your agreement to send mail.

4. Automatic processing

Setting	Details
Process new mail automatically in (one tick box per mailbox)	What it does: each mailbox you tick is watched by Preen. Tick none to keep automatic processing off. Right-click still works in any folder. A summary above shows a pill (Off, Paused or On), the ticked mailboxes, and the settings automatic processing uses: When, Every, Only unread mail, Only mail from the last days, and Dry run. While it is Off or Paused, the settings that do nothing are dimmed, and a note says why. Dry run is never dimmed, because it also decides what right-click Classify does. Change it when: you want Preen to sort new mail without you. Default: none ticked.
Resume	What it does: this button shows when automatic processing is paused. You can pause and resume from the toolbar pop-up and the activity page too. Resume takes effect when you click Save. Change it when: you paused Preen and want it back. Default: not applicable. It shows only when paused.
When	What it does: sets when automatic runs happen. The choices are "As new mail arrives", "On a schedule" and "Only when I click Run now". Change it when: you want faster sorting (as it arrives) or full control (only on Run now). Default: On a schedule.
Every and Unit	What they do: set how often a scheduled run happens. Pick minutes or hours. The range is from 5 minutes to 24 hours. Change it when: you want runs more often or less often. Default: 15 minutes.
Only mail from the last days	What it does: Preen skips mail older than this many days. You can pick 1 to 365. Change it when: you want Preen to look further back, or less far. Default: 2 days.
Only unread mail	What it does: Preen skips mail that you have already read. Change it when: you only want new, unread mail sorted. Default: off.

5. Limits & allowance

Setting	Details
Messages per day (the Daily allowance buttons: Low, Medium, High, Custom)	What it does: the most messages Preen sends in one day. It counts every request: automatic runs, right-click, folders and the toolbar button. The buttons show feathers: one feather is Low, which is 100 a day. Two feathers is Medium, which is 500. Three feathers is High, which is 2,000. A pen is Custom, which shows a box. A zero means no limit. Preen checks the limit before each message, so a request already running may finish after you reach it. Change it when: you want to spend less, or you have a lot of mail. Default: 500 (Medium).
Speed (Low, Medium, High, No limit)	What it does: sets how hard Preen works. It also sets how many waiting messages one automatic run takes. Each button shows one bird. Low is a perched bird, Medium is a gliding bird, High is a bird flying fast, and No limit is a bird riding a rocket.    • Low: one message at a time, 2 seconds of rest after each, 10 messages a run.    • Medium: one message at a time, a short rest after each, 25 messages a run. Preen recommends this.    • High: two at a time, no rest, 50 messages a run.    • No limit: three at a time, no rest, 100 messages a run. Not recommended for big folders or slow computers. Change it when: your computer feels slow, go lower. If you want big folders done sooner, go higher. Default: Medium.

6. Accounts

Setting	Details
Default depth	What it does: sets how much of each message goes to the provider. Surface sends the sender, subject, date, attachment names and header hints. It never sends the message text. Deep adds about 2,000 characters of the message text, in the same request. Change it when: you never want message text to leave your computer. Pick Surface. Default: Deep.
Folders (for each account)	What it does: picks which folders Preen sorts on its own. The choices are "Inbox only", "All folders", "Only these folders…" and "All except these…". The last two show a list of folders with tick boxes. Trash, Junk, Sent, Drafts, Outbox, Templates and Archives are never processed automatically, whatever you pick. Change it when: the previews look right and you want more folders covered. Default: Inbox only.
Depth (for each account)	What it does: lets one account use a different depth. The first choice is "Use default" and it shows what the default is now. Change it when: one account is more private than the others. Default: Use default.
Kind of mailbox (for each account)	What it does: tells Jev what sort of mailbox it is. The choices are Personal, Work, Founder / business owner, Shared or team inbox, and Other. The same email can mean different things in different mailboxes. Your account name and address are never sent. Change it when: the kind of mailbox would help Jev judge your mail. Default: not set.
About this mailbox (optional)	What it does: a short note about the mailbox, sent to Jev as context. It can be up to 128 characters. Change it when: you want to give Jev more hints about the mailbox. Default: empty.

7. People, replies & to-dos

Preen asks Jev three questions about each message. A yes to Real person or Needs reply adds a tag. A yes to the to-do question adds no tag. Preen notes it in the activity log.

Setting	Details
Tag emails from a real person	What it does: adds the Preen/Real person tag when one person wrote to other people. Newsletters, notifications and mail merges do not count. Change it when: you do not want this tag. Default: on.
Certainty required (0 to 1) for real person	What it does: sets how sure Jev must be. Low is 0.6. Medium is 0.7. High is 0.8. Custom lets you type a number. Change it when: you see too many tags (go higher) or too few (go lower). Default: 0.7 (Medium).
Tag emails where someone is waiting for my reply	What it does: adds the Preen/Needs reply tag. Change it when: you do not want this tag. Default: on.
Certainty required (0 to 1) for needs reply	What it does: Low is 0.6. Medium is 0.7. High is 0.8. Custom lets you type a number. Change it when: you see too many wrong tags (go higher) or miss replies (go lower). Default: 0.7 (Medium).
Also flag them (for needs reply)	What it does: also puts a flag on messages tagged Needs reply. Change it when: you want to spot them by their flag. Default: off.
Spot emails that give me something to do	What it does: notes it in the activity log when a message asks you to do something other than reply. Examples are to pay, sign, book, send something or attend. It adds no tag. It flags the message if you turn on Also flag them. Change it when: you do not want Preen to look for this. Default: on.
Certainty required (0 to 1) for to-do	What it does: Low is 0.45. Medium is 0.65. High is 0.75. Custom lets you type a number. Change it when: too many mails count as to-dos (go higher) or too few (go lower). Default: 0.65 (Medium).
Also flag them (for to-do)	What it does: also flags messages Preen spots as a to-do. Flags sync to iCloud, Apple Mail and Gmail as stars. In Thunderbird, Message → Convert to → Task turns one into a task. Change it when: you want to see to-dos by their flag. Default: off.
Sender rules for real person	What it does: you can make a rule for one sender. Right-click a message and choose Preen: this sender is…. Then pick "Always a real person", "Never a real person" or "No rule (let Preen decide)". A rule wins over Jev's answer and saves that question. The settings page lists your rules. Removing a rule takes effect at once. Change it when: Preen keeps getting one sender wrong. Default: no rules.

8. Junk & sensitive info

Both parts are off by default.

Setting	Details
Mark spam, scams and phishing as junk	What it does: adds the Preen/Junk tag and Thunderbird's own Junk mark. Preen never deletes mail. It never clears a junk mark. Junk mail gets no Needs reply tag and is never flagged as a to-do. Jev is told if the sender is in your address book. Change it when: you want Preen to help with spam. Default: off.
Certainty required (0 to 1) for junk	What it does: Low is 0.65. Medium is 0.8. High is 0.9. Custom lets you type a number. Marking real mail as junk is the costly mistake, so the default is high. Change it when: Preen misses junk (go lower) or marks real mail as junk (go higher). Default: 0.9 (High).
Also move it to the Junk folder	What it does: moves mail that Preen marks as junk into the Junk folder. It does this only for real runs, never in dry run. Undo moves it back. Thunderbird asks you to allow moving mail when you tick this. Change it when: you want junk out of your inbox. Default: off.
Allow moving mail	What it does: this button shows if the box above is ticked but Thunderbird has not given Preen permission to move mail. Junk stays where it is until you allow it. Change it when: you ticked the move box and want it to work. Default: not applicable. It shows only when needed.
Note mail that contains personal numbers	What it does: notes "Sensitive" in the activity log when a message shows a payment card number, a bank account number (IBAN), a US Social Security number, a passport number, a driver's licence number or a date of birth. It is checked on your computer only, with no extra cost. It adds no tag and changes nothing on the message. Details without a number, such as a diagnosis, are not detected. Change it when: you want the activity log to show these messages. Default: off.
Replace these numbers before sending	What it does: in the subject and text sent to the AI, each number found this way is replaced with <PII_Block>. It works whether or not the check above is on. Change it when: almost never. Leave it on. Turn it off only if you want those numbers to reach the provider. Default: on.

9. Categories

Categories are your own tags. Categories pick one label for each message. The Real person, Needs reply and Junk questions add yes/no tags on top. Jev picks the category whose description fits best. So the descriptions matter more than the names. Each category is a row. Click a row to open it. A closed row shows its name, the start of its description and its certainty.

Setting	Details
Categories (on/off switch in the section header)	What it does: turns categories on or off. While it is off, Preen asks Jev no category question and gives no category label, so each request is smaller. The yes/no checks you turned on (real person, needs reply, to-do, junk) still run. A note in the section says categories are off, and your category list is kept. Save needs at least one yes/no question turned on while categories are off. See Turning categories off. In an exported settings file this setting is categorySort.enabled. Change it when: you want Preen only for yes/no checks, such as catching junk. Default: on.
Name	What it does: the name of the category. It is also the tag. A category called Bills makes the tag Preen/Bills. A name can have up to 40 characters. A counter beside the box shows how many you have used, such as 12 / 40. It cannot hold / or ". It cannot match a Preen tag name like Junk, Review or To-do. Two names cannot be too alike. Change it when: you add a category or want a better name. Default: the 4 categories listed on Tags and categories.
Is: what belongs here	What it does: says what belongs in the category. It can have up to 128 characters, with a counter. Each row shows "Jev sees" with what Jev will read. Change it when: mail lands in the wrong category. Default: each built-in category has a short description.
Is not: similar mail that belongs elsewhere (optional)	What it does: says what looks alike but does not belong. It can have up to 128 characters. Change it when: a category pulls in the wrong kind of mail. Default: each built-in category has one.
Certainty required (0 to 1) for a category (and its Low, Medium, High, Custom buttons)	What it does: sets how sure Jev must be before this category's tag is added. Low is 0.6. Medium is 0.75. High is 0.9. Change it when: this category tags too much (go higher) or too little (go lower). If you never set it, the category follows the default under Advanced. Default: the default certainty, 0.75 (Medium).
Flag	What it does: flags a message when this category's tag is added. Change it when: you want those messages to stand out. Default: off.
Mark as unread	What it does: marks the message as unread when the tag is added. Preen never marks mail as read, because "read" means you read it. Change it when: you want these messages to stay in front of you. Default: off.
Never a To-do	What it does: stops Preen from counting mail in this category as a to-do, even if Jev thinks it is one. Change it when: a category is rarely a real task. Default: on for Codes. Off for the rest.
Move up, Move down and Remove	What they do: change the order of categories, or delete one. You cannot remove the last category. Change it when: you want to tidy the list. Default: not applicable. They are buttons.
Add category	What it does: adds an empty category. You can have up to 20. Change it when: you want a tag Preen does not have. Default: not applicable. It is a button.
Reset to defaults	What it does: puts the category list back to the 4 built-in ones. Change it when: you want to start over. Default: not applicable. It is a button.

10. Privacy & data

This section also lists what Jev sees. See Privacy and data.

Setting	Details
Personal context about you (optional)	What it does: a few words about you. Preen sends them with every request so Jev can judge mail from your point of view. It can have up to 128 characters. Change it when: it would help Jev, for example if you mention your job. Default: empty. Nothing is sent.
Languages I read (optional)	What it does: the languages you read. Preen sends them with every request as a hint, not a rule. It can have up to 200 characters. Change it when: you get mail in other languages. Default: empty. The first time, Preen fills it in from your Thunderbird and browser language settings. If it is empty, nothing is sent.
History kept: Days (with Low, Medium, High, Custom)	What it does: how long Preen keeps its activity log. Older entries are removed. Low is 30 days. Medium is 90 days. High is a year. Monthly token totals are kept either way. You can type 1 to 3650 days. Change it when: you want a shorter or longer record. Default: 90 days (Medium).
Tag processed messages so other computers skip them too	What it does: adds a small tag, Preen: processed, to each message Preen has handled. On IMAP accounts the tag syncs to your other computers, so they skip those messages. Gmail does not keep tags, so on Gmail all Preen tags, this one too, stay in this Thunderbird. A local record is always kept. Change it when: you use Thunderbird on more than one computer, keep it on. If you do not want an extra tag, turn it off. Default: on.

11. Tag corrections

When you add or remove a Preen tag yourself, Preen notes it. It writes down the tag, your change and its own score. It stores no sender, subject or text. This stays on your computer. Preen also remembers, on your computer, which messages you corrected. It does not tag them again in automatic runs or Classify with Preen. It tells you how many it skipped and offers Classify anyway. Preview still works on them. Corrections are kept for 2 years. Clear history does not remove them. With enough corrections, Preen can suggest a level for a tag. A suggestion appears after 10 corrections for that tag. A suggestion changes nothing until you click Apply and then Save.

Setting	Details
Export corrections (CSV) and Export corrections (JSON)	What they do: save your corrections to a file so you can see where Preen gets it wrong. Change it when: you want to look at your corrections. Default: not applicable. They are buttons.
Clear corrections…	What it does: deletes all recorded corrections, after you confirm. The suggestions start over. You cannot undo this. Change it when: you want a fresh start. Default: not applicable. It is a button.

12. Statistics

This section shows your own numbers. Preen sends no usage statistics.

Setting	Details
Your totals	What it does: shows a table with two columns. The first is named for the current month, such as "October 2026". The second starts where your totals begin, such as "Since September 2026". The rows are Messages sorted, Tokens, Estimated cost, Messages changed, Real person tags, Needs reply tags, To-do messages, Marked as junk and Your tag corrections. Below it you see the date you started using Preen, the date you last reset the statistics, the date the history starts, and how many messages are in each category. Then come small tables, with the same columns:    • Errors: failed messages by kind, one per message. Also messages not tried after an error.    • Skipped or text not sent: by reason, like Limit reached, Encrypted or You corrected it. "You corrected it" counts messages Preen left alone because you changed their tags yourself.    • Runs: by type, and if they were automatic or started by you.    • Corrections by tag: your fixes for each tag kind. All category tags count together. A separate table, Decided without a tag, shows how many messages were marked for review (no category).    • Depth and undo: messages sorted at Surface and at Deep, runs undone and messages put back.    • Response time: how long the provider took for each message. Only providers you used are shown. Change it when: not applicable. You cannot change it. Default: Preen counts these on your computer. Only you see them.
Reset my statistics	What it does: after you confirm, it clears the monthly totals shown above. Your activity log and your tag corrections are kept. You cannot undo it. Until new mail is sorted, the second column is headed with the date of the reset. Change it when: you want your totals to start again from zero. Default: not applicable. It is a button.
Undo last run	What it does: puts the messages from Preen's most recent applied run back how they were. Tags or changes you made yourself are left alone. Older runs can be undone from the activity log. The toolbar pop-up has the same button. Change it when: the last run did something you do not want. Default: not applicable. It is a button.

13. Backup

Setting	Details
Export settings…	What it does: saves your settings to a file. Change it when: you want a backup, or you want to move settings to another computer. Default: not applicable. It is a button.
Include my API key	What it does: puts your API key in the exported file, in plain text. Anyone with that file can use your key. Change it when: almost never. Leave it off unless you trust where the file goes. Default: off. The key is left out.
Import settings…	What it does: loads settings from a file. Preen shows them for you to review. They take effect only when you click Save. Change it when: you want to restore a backup. Default: not applicable. It is a button.

14. Debug

Setting	Details
Keep a debug log	What it does: stores each request sent to Jev and its answer exactly. That includes the full message text. It also stores Preen's decision and your settings, but never your API key. It stays on this computer and is kept as long as the history. It takes effect at once. A banner shows while it is on. On the activity page, View raw exchange shows a row's request and answer. Change it when: you are troubleshooting. Turn it off when you are done. Default: off.
Keep records and Delete records	What they do: when you turn debug off, Preen asks if you want to keep the records already stored or delete them. Change it when: you turn debug mode off. Default: not applicable. They show only when you turn debug off.
Export debug log (JSON)	What it does: saves the debug log to a file. The file holds message text, so share it only with someone you trust. Change it when: you need to look at the exact requests. Default: not applicable. It is a button.
Clear debug log	What it does: deletes the debug log. Change it when: you are done troubleshooting. Default: not applicable. It is a button.

15. Advanced

Setting	Details
Default certainty for categories (0 to 1)	What it does: the certainty used by every category that has none of its own. An answer very close to a threshold (within 0.15) is noted as "unsure" in the activity log. Change it when: most of your categories tag too much or too little. Default: 0.75.
Appearance	What it does: sets the colours of every Preen page. The choices are "Match Thunderbird", "Light" and "Dark". Change it when: you want Preen to look different from Thunderbird. Default: Match Thunderbird.
Dry run	What it does: while it is on, Classify with Preen and automatic processing only log what they would do. They change nothing. Turning it off asks first. The question warns that Preen will start adding tags, flags and unread marks. Turn off goes ahead. Keep dry run on cancels. Change it when: you want Preen to only log what it would do. Default: off.