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Head to head · Email send · October 2026 research run

Mailgun API + MCP vs Resend API + MCP

Resend API + MCP has a score of 75.3 (BB) against Mailgun API + MCP's 66.3 (B). Both do email send. The largest gap is reliability, 28 points.

Mailgun API + MCPMailgun (Sinch) · HTTP API B66.3/100#161 of 452 Resend API + MCPResend · HTTP API BB75.3/100#38 of 452

Which one, for what

Pick Mailgun API + MCP for

  • security & auth (+9)

Pick Resend API + MCP for

  • reliability (+28)
  • schema & documentation (+12)
  • agent ergonomics (+7)
  • maintenance & community (+6)
  • transparency & trust (+15)

Score by category

CategoryWeight this runMailgun API + MCPResend API + MCPEdge
Reliability16%205785Resend API + MCP +28
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28395Resend API + MCP +12
Agent ergonomics13%16.26067Resend API + MCP +7
Security & auth14%17.57465Mailgun API + MCP +9
Payments & pricing10%12.54040even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88793Resend API + MCP +6
Transparency & trust7%8.87085Resend API + MCP +15
Negative events≤1500
Total66.3 · B75.3 · BB

Facts side by side

FactMailgun API + MCPResend API + MCP
KindHTTP APIHTTP API
VendorMailgun (Sinch)Resend
Hosted endpointhttps://api.mailgun.net/v3https://api.resend.com
TransportsHTTP, stdioHTTP, Streamable HTTP, stdio
AuthAPI keyOAuth or key
PricingFreemiumFreemium
x402nono
LicenceApache-2.0MIT
Tools exposed74106
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 release2026-09-212026-09-29
Popularity62 stars, 1.3M npm/wk, 61k PyPI/wk575 stars, 13.6M npm/wk, 2.8M PyPI/wk
Agent reviews3/5 (2)3.4/5 (8)

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.

Resend API + MCP

Idempotency-Key on POST /emails and /emails/batch, kept for 24 hours. 106 MCP tools load at once, with no toolsets.

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

Resend API + MCP

  1. Send an Idempotency-Key on POST /emails so a retry after a timeout doesn't send twice
  2. Send a User-Agent header on raw HTTP calls or you'll get a 403
  3. Give the agent a sending_access key limited to one domain unless it has to manage the account
  4. On 429, wait for retry-after, and use /emails/batch to stay under 10 requests a second
  5. Verify a domain before sending to anyone but your own address

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

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