Warmup Mailboxes

> Before running: verify exact flag names with smartlead --help. Flag shapes shown below are illustrative — confirm against the actual CLI.

/warmup-mailboxes

You're configuring warmup on one or more Smartlead mailboxes using a verified production-grade config.

What you need from the user

• Mailbox IDs — comma-separated, or a tag/client filter
• Warmup pool key — a 5-letter-prefix-5-letter-suffix tag like acme1-pool1 (groups mailboxes that warm up together)
• Optionally: client_id if the mailboxes need to be assigned to a Smartlead client record

Ask for these if not provided.

The golden config we'll apply

Verified for Gmail mailboxes. Before applying, check the mailbox type — if it's not GMAIL, pause and ask the user how they want to proceed.

message_per_day: 15           # not 20 — leave buffer for warmup
warmup_enabled: true
warmup_min_count: 1
warmup_max_count: 20
daily_rampup: 5               # 1 → 6 → 11 → 16 → 20 over 5 days
reply_rate: 60                # 60% reply rate from warmup network
auto_adjust_warmup: false     # manual control beats automatic
send_warmups_only_on_weekdays: true
use_custom_domain: false      # OFF during warmup, turn on week 4+
daily_reply_limit: 5

Why these values: see docs/learnings/mailbox-warmup-best-practices.md.

How to run it

For a single mailbox

smartlead accounts warmup  --enable \
  --daily 20 --rampup 5 --reply-rate 60 \
  --warmup-key 

For many mailboxes (uses the internal bulk endpoint)

smartlead accounts bulk-update \
  --ids ,, \
  --message-per-day 15 \
  --warmup-status ENABLED \
  --warmup-min 1 \
  --warmup-max 20 \
  --rampup-value 5 \
  --reply-rate 60 \
  --warmup-key  \
  --send-warmups-only-on-weekdays

Filter by tag (if mailboxes are pre-tagged)

# Find IDs by tag
smartlead accounts tags get --tag  --output json | jq -r '.[].id' > ids.txt

# Then bulk-update
smartlead accounts bulk-update --ids-file ids.txt ...

After warming up

After ~3 weeks of clean warmup, the mailbox is ready for production. At that point:

# Turn on custom-domain tracking (was off during ramp)
smartlead accounts bulk-update --ids  --use-custom-domain

Verification

smartlead accounts get  --output json | jq '.warmup_details'

Should show:

• warmup_enabled: true
• total_warmup_per_day: 20
• warmup_min_count: 1
• warmup_max_count: 20
• daily_rampup: 5
• warmup_key_id: ""

Notes

• The public warmup API enforces daily_rampup >= 5. To use lower rampup values you must use the internal bulk endpoint (which the bulk-update command uses by default).
• warmup_key_id controls which mailboxes pool together for warmup. Pick keys deliberately — see docs/learnings/warmup-key-id-format.md.
• For a deep dive on why send 15 (not 20) and why weekday-only, see docs/learnings/mailbox-warmup-best-practices.md.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: MattSezgin
• Source: MattSezgin/unofficial-smartlead-cli
• License: MIT
• Homepage: https://github.com/MattSezgin/unofficial-smartlead-cli

Install and usage instructions live in the source repository linked above.