Mailtrap alternative for AI agents: AgentiSend compared (2026)
Is AgentiSend a Mailtrap alternative?
Yes, AgentiSend is a Mailtrap alternative for transactional email an agent sends through an API, while Mailtrap is the product whose sandbox never delivers a message. POST /emails/preflight runs every send gate and does not send the message. A Free plan that does not expire: 3,000 emails a month, 100 a day, 3 domains, no card. Then plans from $9 a month (Starter, 30,000 emails). No plan daily cap; delivery paced per inbox provider. Or 40% off paid yearly.
Pick Mailtrap when you want a sandbox whose messages never reach a real inbox, inbound mail on the free plan, or a SOC 2 Type II report on every plan; pick AgentiSend when an agent holds the key and you want a per-key budget and a kill switch. The figures below are from Mailtrap pages fetched on 21 October 2026 and from this product's pricing table and published API.
| What matters | AgentiSend | Mailtrap |
|---|---|---|
| A spending limit per key | Every key is created with a send budget. The send path refuses with agent_budget_exceeded when it is spent, and a key cannot raise its own. The plan inclusion is a second ceiling (plan_limit_reached). | A per-key send budget is not on the pricing plans page. The rate-limits page sets 150 requests per 10 seconds per API token, shared by every endpoint, which is a request cap rather than a send budget. |
| What a refusal tells you | Every refused request carries code, message, fix (the call that repairs it), docs_url and retryable. | A failed send returns success set to false and an errors array of strings. The bad-request response says to fix the errors listed before retrying. A field named fix that names the next call is not on that page. |
| A retry never sends twice | Idempotency-Key is accepted on every endpoint that changes something and remembered for 7 days. | The send transactional page does not document an idempotency key. A repeated call is not described as returning the first result. |
| How long the log keeps a message | 7 days on Free, 30 on Starter, 90 on Pro, 180 on Scale. It is part of the plan and there is no add-on to buy. | Email log retention is 3 days on Free, 5 days on Basic, 15 days on Business, and 30 days on Enterprise. |
Read further
- AgentiSend vs Mailtrap: all 10 rows, with a source for each.
- Pricing: every plan and limit.
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