# InboxAPI vs MailSlurp (slim)

> MailSlurp scores 68.4 (B) to InboxAPI's 54.5 (C) for agent inboxes. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/inboxapi-vs-mailslurp.md (~2,200 tokens) · this version ~680 tokens · JSON https://www.anchorterminal.com/compare/inboxapi-vs-mailslurp.json · canonical https://www.anchorterminal.com/compare/inboxapi-vs-mailslurp
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

MailSlurp scores 68.4 (B) on agent readiness against InboxAPI's 54.5 (C), and leads in 6 of 7 scored categories. InboxAPI leads on payments & pricing. Both do agent inboxes.

- InboxAPI: C 54.5, rank #684 of 950 · https://www.anchorterminal.com/tools/inboxapi.min.md
- MailSlurp: B 68.4, rank #215 of 950 · https://www.anchorterminal.com/tools/mailslurp.min.md
- InboxAPI, good for A personal mailbox for one coding agent that needs to exchange mail with its owner and a few contacts at no cost. Ahead on Payments & pricing, 53 against 32. Also No key needed to call it; Runs on your own machine; Free to start without a card.
- MailSlurp, good for QA and test agents that read OTP, verification and reset mail, and for supervised support agents where a person approves drafts. Ahead on Reliability, 75 against 33; Agent ergonomics, 84 against 61; Security & auth, 70 against 57; Maintenance & community, 75 against 63; Transparency & trust, 60 against 53.

| Category | InboxAPI | MailSlurp |
| --- | --- | --- |
| Reliability (16%) | 33 | 75 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 69 | 72 |
| Agent ergonomics (13%) | 61 | 84 |
| Security & auth (14%) | 57 | 70 |
| Payments & pricing (10%) | 53 | 32 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 63 | 75 |
| Transparency & trust (7%) | 53 | 60 |

| Fact (where they differ) | InboxAPI | MailSlurp |
| --- | --- | --- |
| Kind | MCP server | HTTP API |
| Vendor | Sitka Capital Pty Ltd | Pettman OÜ |
| Hosted endpoint | `https://mcp.inboxapi.ai/mcp` | `https://api.mailslurp.com` |
| Transports | stdio, Streamable HTTP | HTTP, Streamable HTTP |
| Auth | None | OAuth or key |
| Pricing | Free | Freemium |
| Price for agent inboxes | free | $1 per transaction |
| Licence | Proprietary hosted service under InboxAPI's terms of service. The CLI on GitHub is MIT | Proprietary service under MailSlurp's terms. The JavaScript client on GitHub is MIT |
| Tools exposed | 21 | 16 |
| Last release | 2026-09-22 | 2026-09-24 |
| Terms last updated | 2026-09-11 | 2026-01-16 |
| Privacy policy last updated | 2026-09-11 | 2026-01-16 |
| Arbitration or class-action waiver | not found in the text | yes |
| Popularity | 12 stars, 38 npm/wk | 201k npm/wk |