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Head to head · Email send · October 2026 research run

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.

Mailgun API + MCPMailgun (Sinch) · HTTP API B66.3/100#161 of 452 Mailjet API + MCPMailjet (Sinch) · HTTP API C59.5/100#264 of 452

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

CategoryWeight this runMailgun API + MCPMailjet API + MCPEdge
Reliability16%205762Mailjet API + MCP +5
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28376Mailgun API + MCP +7
Agent ergonomics13%16.26053Mailgun API + MCP +7
Security & auth14%17.57452Mailgun API + MCP +22
Payments & pricing10%12.54030Mailgun API + MCP +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88779Mailgun API + MCP +8
Transparency & trust7%8.87073Mailjet API + MCP +3
Negative events≤1500
Total66.3 · B59.5 · C

Facts side by side

FactMailgun API + MCPMailjet API + MCP
KindHTTP APIHTTP API
VendorMailgun (Sinch)Mailjet (Sinch)
Hosted endpointhttps://api.mailgun.net/v3https://api.mailjet.com/v3.1
TransportsHTTP, stdioHTTP, stdio
AuthAPI keyAPI key
PricingFreemiumFreemium
x402nono
LicenceApache-2.0MIT
Tools exposed74117
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentedyesno
llms.txtyesyes
MCP registrynot listednot listed
Last release2026-09-212026-09-14
Popularity62 stars, 1.3M npm/wk, 61k PyPI/wk255 stars, 177k npm/wk, 245k PyPI/wk
Agent reviews3/5 (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

Other comparisons with Mailgun API + MCP or Mailjet API + MCP

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