Coldrig vs AgentMail: an inbox API vs. the whole cold-email job
AgentMail gives an AI agent its own programmable inbox. It is not a cold-email platform, so this page does not set the two against each other on price. With Coldrig, your assistant buys and sets up the domains and Google mailboxes, they warm up, and it sends, follows up, and handles replies and unsubscribes.
Does AgentMail do the same job?
The job is mailboxes, domains, warmup and sending, run by an assistant with nothing done by hand. On AgentMail's pricing page, the answer is no for most of it.
| Part of the job | AgentMail | Coldrig |
|---|---|---|
| A programmable inbox for an agent | Yes. This is the product ("Email Inboxes for AI Agents"), with SDKs and an MCP server in its feature list. | Yes, as one part of the job. |
| Buys and sets up domains and mailboxes | Not listed. The pricing page lists inboxes and custom domains as plan limits, and no domain purchase. | Yes. Your assistant does it with setup_infrastructure. |
| Warmup | Not listed on the pricing page. | Yes, built in, a ramp of about four weeks per mailbox. |
| Campaigns, follow-ups, sequences | Not listed on the pricing page. | Yes, through launch_campaign. |
If an agent needs an inbox of its own to send, receive, and search email, AgentMail fits that. If it needs cold email run end to end, the pricing page lists nothing for the other parts of the job.
Prices, side by side
These prices buy different things, so this page does not rank them.
| AgentMail plan (read 2026-10-14) | Price | What the pricing page lists |
|---|---|---|
| Free | $0 a month | 3 inboxes, 3,000 emails a month (100 a day), 3 GB storage. |
| Developer | $20 a month | 10 inboxes, 10,000 emails a month (1,000 a day), 10 GB storage, 10 custom domains, 2 organization seats, email support. |
| Startup | $200 a month | 150 inboxes, 150 custom domains, 15,000 emails a day, 10 organization seats, SOC 2 report. |
| Enterprise | Custom | Everything in Startup, plus unlimited inboxes, dedicated IPs and SSO. |
AgentMail add-ons are $2 a month per inbox or domain and $2 a month per 1,000 emails. Coldrig: $49 a month for 3 mailboxes, $59 for 5, $84 for 10, $134 for 20 and $334 for 60. That one price covers the mailboxes, their domains, warmup and sending, with $0 per-send fees.
Bottom line
Choose AgentMail when an agent needs a raw inbox. Choose Coldrig when you want cold email run end to end by your assistant. Re-run this comparison if AgentMail adds warmup or campaign sending to its pricing page.
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