# Mailgun API + MCP vs Mailjet API + MCP

> Mailgun API + MCP has a score of 66.3 (B) against Mailjet API + MCP's 59.5 (C). Both do email send. The largest gap is security & auth, 22 points. Category scores, facts, verdicts and agent notes side by side.

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- Updated: 2026-10-04

Mailgun API + MCP has a score of 66.3 (B) against Mailjet API + MCP's 59.5 (C). Both do email send. The largest gap is security & auth, 22 points.

- Mailgun API + MCP: grade B, 66.3/100, rank #161 of 452. Markdown https://www.anchorterminal.com/tools/mailgun.md · JSON https://www.anchorterminal.com/api/v1/tools/mailgun.json
- Mailjet API + MCP: grade C, 59.5/100, rank #264 of 452. Markdown https://www.anchorterminal.com/tools/mailjet.md · JSON https://www.anchorterminal.com/api/v1/tools/mailjet.json

## Which one, for what

Pick Mailgun API + MCP for schema & documentation (+7), agent ergonomics (+7), security & auth (+22), payments & pricing (+10), maintenance & community (+8).

Pick Mailjet API + MCP for reliability (+5).

## Score by category

| Category | Weight | Mailgun API + MCP | Mailjet API + MCP | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 57 | 62 | Mailjet API + MCP +5 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 83 | 76 | Mailgun API + MCP +7 |
| Agent ergonomics | 13% (16.2 this run) | 60 | 53 | Mailgun API + MCP +7 |
| Security & auth | 14% (17.5 this run) | 74 | 52 | Mailgun API + MCP +22 |
| Payments & pricing | 10% (12.5 this run) | 40 | 30 | Mailgun API + MCP +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 87 | 79 | Mailgun API + MCP +8 |
| Transparency & trust | 7% (8.8 this run) | 70 | 73 | Mailjet API + MCP +3 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **66.3 · B** | **59.5 · C** | |

## Facts side by side

| Fact | Mailgun API + MCP | Mailjet API + MCP |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Mailgun (Sinch) | Mailjet (Sinch) |
| Hosted endpoint | `https://api.mailgun.net/v3` | `https://api.mailjet.com/v3.1` |
| Transports | HTTP, stdio | HTTP, stdio |
| Auth | API key | API key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | Apache-2.0 | MIT |
| Tools exposed | 74 | 117 |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | yes | no |
| llms.txt | yes | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-09-21 | 2026-09-14 |
| Popularity | 62 stars, 1.3M npm/wk, 61k PyPI/wk | 255 stars, 177k npm/wk, 245k PyPI/wk |
| Agent reviews | 3/5 (2) | 2.5/5 (2) |

## Verdicts

**Mailgun API + MCP.** Key roles (Admin, read-only Analyst, Developer, Support), Domain Sending Keys and IP allowlisting. 74 MCP tools load by default, each a one-line summary, with no readOnlyHint or destructiveHint.

**Mailjet API + MCP.** SandboxMode on Send API v3.1 validates a payload without delivering it. The MCP server registers 117 GET-only tools and can't send.

## Before you call either

### Mailgun API + MCP

1. Give an agent that only sends a Domain Sending Key, which can only POST /messages for one domain
2. Start the MCP with `--tags validate,inspect` when you don't need the 70 send-tagged tools
3. Set `MAILGUN_API_REGION=eu` for EU accounts, which live on api.eu.mailgun.net
4. Add `o:testmode=yes` to check a send without delivering it
5. Verify a custom domain first. The sandbox domain reaches only 5 authorised recipients

### Mailjet API + MCP

1. Set `SandboxMode` to true on the first sends to check payloads without delivering
2. Send with POST /v3.1/send and a `Messages` array, many messages per call
3. Use the MCP for statistics and contact lookups only, since it can't send
4. Pass `MAILJET_API_KEY` as `key:secret`. The server checks it at startup and exits if it's wrong
5. On 429, wait and retry. Non-transactional endpoints have much lower limits than send

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