Reported ranking
Best and worst sites for AI agents to dev saas api / read email api docs.
Ranked from recent CrawlDex observations. Last verified Jun 27, 2026. Based on 5 observations.
Publication status
More data needed- 5
- ranked websites
- 100
- best AES
- 0
- hardest AES
- 21%
- board handoff share
Search indexing requires at least eight recent qualifying rows. This page still serves the full table for agents and humans when the count is lower.
Ranked table
All ranked sites for agents trying to dev saas api / read email api docs
Outcome signal is shown on the same 0-100 scale as the public AES board until split outcome rates are exposed by the board feed.
| Rank | Site | AES | Outcome signal | Top blocker | Last verified |
|---|---|---|---|---|---|
| 1 | Mailgun mailgun.com | 100 | 100% | public url verified | Jun 21, 2026 |
| 2 | Docs Sendgrid docs.sendgrid.com | 80 | 80% | public url verified | Jun 27, 2026 |
| 3 | Resend resend.com | 80 | 80% | public url verified | Jun 21, 2026 |
| 4 | Sendgrid sendgrid.com | 80 | 80% | public url verified | Jun 21, 2026 |
| 5 | Postmarkapp postmarkapp.com | 0 | 0% | public url verified | Jun 21, 2026 |
Worst-of section
The hardest reported sites for AI agents
AES 0
Postmarkapp
Top blocker: public url verified. Last verified Jun 21, 2026. Low confidence, 1 observations.
AES 80
Sendgrid
Top blocker: public url verified. Last verified Jun 21, 2026. Low confidence, 1 observations.
AES 80
Resend
Top blocker: public url verified. Last verified Jun 21, 2026. Low confidence, 1 observations.
AES 80
Docs Sendgrid
Top blocker: public url verified. Last verified Jun 27, 2026. Low confidence, 1 observations.
AES 100
Mailgun
Top blocker: public url verified. Last verified Jun 21, 2026. Low confidence, 1 observations.