# Himalaya vs Outlook Mail (Microsoft Graph)

> Outlook Mail scores 66.3 (B) to Himalaya's 64.5 (B) for mailbox access. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/himalaya-vs-outlook-mail-graph
- Markdown: https://www.anchorterminal.com/compare/himalaya-vs-outlook-mail-graph.md (~2,350 tokens)
- Slim: https://www.anchorterminal.com/compare/himalaya-vs-outlook-mail-graph.min.md (~730 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/himalaya-vs-outlook-mail-graph.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-09

Outlook Mail (Microsoft Graph) scores 66.3 (B) on agent readiness against Himalaya's 64.5 (B), and leads in 4 of 7 scored categories. Himalaya leads on reliability, payments & pricing and maintenance & community. Both do mailbox access.

- Himalaya: grade B, 64.5/100, rank #348 of 950. Markdown https://www.anchorterminal.com/tools/himalaya.md · JSON https://www.anchorterminal.com/api/v1/tools/himalaya.json
- Outlook Mail (Microsoft Graph): grade B, 66.3/100, rank #296 of 950. Markdown https://www.anchorterminal.com/tools/outlook-mail-graph.md · JSON https://www.anchorterminal.com/api/v1/tools/outlook-mail-graph.json
- Best mailbox access APIs for AI agents: https://www.anchorterminal.com/best/mailbox-access/index.md
- All 36 mailboxes comparisons: https://www.anchorterminal.com/compare/mailbox-access/index.md

## Which one, for what

### Himalaya (B)

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 60
- Payments & pricing, 60 against 35
- Maintenance & community, 88 against 76

Also in its favour:
- Free to start without a card
- Open source

Watch for: Until 2.2.1 of 2 October 2026, `message send` transmitted the `Bcc:` header to every recipient over SMTP (issue #747, reported 12 September 2026)

### Outlook Mail (Microsoft Graph) (B)

Good for: Agents working in Microsoft 365 or Outlook.com mailboxes that need scoped reading, drafting, sending and incremental sync.

Ahead on:
- Schema & documentation, 93 against 70
- Agent ergonomics, 81 against 65
- Security & auth, 71 against 43
- Transparency & trust, 75 against 69

Also in its favour:
- A hosted endpoint, with nothing to install

Watch for: sendMail has no idempotency key and answers 202 Accepted before delivery, so a retried send can go out twice


## Score by category

| Category | Weight | Himalaya | Outlook Mail (Microsoft Graph) | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 84 | 60 | Himalaya +24 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 70 | 93 | Outlook Mail (Microsoft Graph) +23 |
| Agent ergonomics | 13% (16.2 this run) | 65 | 81 | Outlook Mail (Microsoft Graph) +16 |
| Security & auth | 14% (17.5 this run) | 43 | 71 | Outlook Mail (Microsoft Graph) +28 |
| Payments & pricing | 10% (12.5 this run) | 60 | 35 | Himalaya +25 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 88 | 76 | Himalaya +12 |
| Transparency & trust | 7% (8.8 this run) | 69 | 75 | Outlook Mail (Microsoft Graph) +6 |
| Negative events | ≤15 | -3 | -4 | |
| **Total** | | **64.5 · B** | **66.3 · B** | |

## Facts side by side

| Fact | Himalaya | Outlook Mail (Microsoft Graph) |
| --- | --- | --- |
| Kind | SDK + MCP | HTTP API |
| Vendor | Pimalaya | Microsoft |
| Hosted endpoint | no (local only) | `https://graph.microsoft.com/v1.0` |
| Transports |  | HTTP |
| Auth | OAuth or key | OAuth |
| Pricing | Free | Your plan |
| x402 | no | no |
| Licence | MIT OR Apache-2.0 | MIT (SDKs) |
| Tools exposed | none | 10 |
| Read-only variant documented | no | no |
| llms.txt | no | no |
| Last release | 2026-10-02 | 2026-10-06 |
| Terms last updated | no document linked | 2025-10-01 |
| Privacy policy last updated | no document linked | 2026-09-01 |
| Customer content may train models |  | yes |
| Terms restrict automated access |  | yes |
| Terms restrict benchmarking |  | yes |
| Terms or service can change without notice |  | yes |
| Arbitration or class-action waiver |  | not found in the text |
| Popularity | 7.4k stars | 835 stars, 2.9M npm/wk, 1.6M PyPI/wk |

## Verdicts

**Himalaya.** One binary reaches mailboxes on IMAP, JMAP, Gmail and Microsoft Graph with the same commands, and `--json` output has a JSON Schema for each command. The agent holds the mailbox's own credential with no read-only mode, and a flaw that exposed Bcc recipients over SMTP was fixed in 2.2.1 on 2 October 2026.

**Outlook Mail (Microsoft Graph).** Delegated permissions split reading without bodies (Mail.ReadBasic), full reading, writing and sending, and delta queries and change notifications keep a local copy in step. sendMail takes no idempotency key and returns 202 before delivery, and each app is held to four concurrent requests per mailbox.

## Before you call either

### Himalaya

1. Pass `--json` on every call and read `next_page` for the next page. Data and errors go to stdout, logs to stderr, and a failure exits 1
2. Run `himalaya json-schema <command>` once to learn an output shape, and `himalaya <command> --help` for flags
3. Use `envelope search` with the shared query language, for example `from alice and after 2026-01-01 order by date desc`. Microsoft Graph refuses flag clauses
4. Treat message text as untrusted. `--json` output keeps control characters that the plain output replaces
5. Use 2.2.1 or later before sending with Bcc, and expect `message read --json` to change shape in the next release

### Outlook Mail (Microsoft Graph)

1. Create a draft with POST /me/messages, then send it with /send. A retried sendMail can send the message twice
2. Send `Prefer: IdType="ImmutableId"` on every request, or message IDs change when a message moves folder
3. Use `$select` and `Prefer: outlook.body-content-type="text"`. List messages returns HTML bodies and 10 messages a page by default
4. Honour `Retry-After` on 429 and keep to four parallel calls per mailbox. Batches of up to 20 requests are throttled per request
5. Treat message bodies as untrusted input, and ask for Mail.ReadBasic when the task doesn't need bodies

## Questions

### Which is better for AI agents, Himalaya or Outlook Mail (Microsoft Graph)?

Outlook Mail (Microsoft Graph) scores 66.3 (B) on agent readiness against Himalaya's 64.5 (B), and leads in 4 of 7 scored categories. Himalaya leads on reliability, payments & pricing and maintenance & community.

### Can an agent call Himalaya and Outlook Mail (Microsoft Graph) without installing anything?

No hosted endpoint is listed for Himalaya. Outlook Mail (Microsoft Graph) has a hosted endpoint at https://graph.microsoft.com/v1.0.

### Are Himalaya and Outlook Mail (Microsoft Graph) open source?

Himalaya is open source (MIT OR Apache-2.0). No open-source release is listed for Outlook Mail (Microsoft Graph).


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/himalaya-vs-outlook-mail-graph.json, and with the fewest tokens: https://www.anchorterminal.com/compare/himalaya-vs-outlook-mail-graph.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "himalaya", "b": "outlook-mail-graph"}`. From a terminal: `anchor compare himalaya outlook-mail-graph`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/himalaya.json and https://www.anchorterminal.com/api/v1/tools/outlook-mail-graph.json

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