# Fastmail API (JMAP) vs Himalaya (slim)

> Himalaya scores 64.5 (B) to Fastmail's 54.1 (C) for mailbox access. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/fastmail-vs-himalaya.md (~2,350 tokens) · this version ~780 tokens · JSON https://www.anchorterminal.com/compare/fastmail-vs-himalaya.json · canonical https://www.anchorterminal.com/compare/fastmail-vs-himalaya
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

Himalaya scores 64.5 (B) on agent readiness against Fastmail API (JMAP)'s 54.1 (C), and leads in 4 of 7 scored categories. Fastmail API (JMAP) leads on agent ergonomics, security & auth and transparency & trust. Both do mailbox access.

- Fastmail API (JMAP): C 54.1, rank #694 of 950 · https://www.anchorterminal.com/tools/fastmail.min.md
- Himalaya: B 64.5, rank #348 of 950 · https://www.anchorterminal.com/tools/himalaya.min.md
- Fastmail API (JMAP), good for An agent working in its owner's own Fastmail mailbox, where JMAP gives batched reads, structured search and state-based sync on an open standard, and MCP gives a ready connection with read, write and send levels. Ahead on Agent ergonomics, 73 against 65; Security & auth, 60 against 43; Transparency & trust, 74 against 69. Also No incidents deducted, where Himalaya loses 3 points for them.
- Himalaya, good for An agent with a shell that must work in one person's existing mailbox on any provider, including plain IMAP hosts, without a hosted intermediary. Ahead on Reliability, 84 against 54; Schema & documentation, 70 against 52; Payments & pricing, 60 against 30; Maintenance & community, 88 against 26. Also Free to start without a card; Open source.

| Category | Fastmail API (JMAP) | Himalaya |
| --- | --- | --- |
| Reliability (16%) | 54 | 84 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 52 | 70 |
| Agent ergonomics (13%) | 73 | 65 |
| Security & auth (14%) | 60 | 43 |
| Payments & pricing (10%) | 30 | 60 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 26 | 88 |
| Transparency & trust (7%) | 74 | 69 |

| Fact (where they differ) | Fastmail API (JMAP) | Himalaya |
| --- | --- | --- |
| Kind | HTTP API | SDK + MCP |
| Vendor | Fastmail Pty Ltd | Pimalaya |
| Transports | HTTP |  |
| Pricing | Paid | Free |
| Licence | Proprietary service under Fastmail's API Terms of Service and API Developer Policy. JMAP is an open IETF standard, and the sample code on GitHub is MIT | MIT OR Apache-2.0 |
| Read-only variant documented | yes | no |
| Last release | 2026-04-22 | 2026-10-02 |
| Terms last updated | no date given | no document linked |
| Privacy policy last updated | no date given | no document linked |
| Customer content may train models | not found in the text |  |
| Terms restrict automated access | not found in the text |  |
| Terms restrict benchmarking | yes |  |
| Terms or service can change without notice | not found in the text |  |
| Arbitration or class-action waiver | not found in the text |  |
| Popularity | 123 stars | 7.4k stars |