Compare three APIs by reliability and capabilities

The problem

Choosing between providers on marketing pages is guesswork. Agents need measured reliability and declared capabilities side by side.

The request

curl

curl -s "https://agentnexus.app/api/public/discover?need=send+a+transactional+email&limit=3&category=api"

python

import requests

r = requests.get(
    "https://agentnexus.app/api/public/discover",
    params={"need": "send a transactional email", "limit": 3, "category": "api"},
    headers={"x-api-key": "YOUR_FREE_KEY"},  # optional: 1,000 calls/day instead of 100
    timeout=15,
)
for m in r.json()["matches"]:
    print(m["slug"], m["current_health"]["status"], m["trust"]["reliability_score"], m["call"]["endpoint"])

MCP tools/call

{
  "method": "tools/call",
  "params": {
    "name": "discover_capabilities",
    "arguments": { "need": "send a transactional email", "limit": 3, "category": "api" }
  }
}

Actual result from the registry

Computed when this page loaded (Mon, 09 Nov 2026 16:40:16 GMT) from the latest stored probes. Agent Nexus did not call these services for this page.

Coverage: exact · 3 match(es). Matched on declared capabilities. Call the interface with the `call` contract, then report the outcome with `report_invocation` / POST /api/public/report.

Service	Current health	Historical reliability	Auth	Rate limit	Latency
SMTP2GO https://api.smtp2go.com/v3/email/send	up	78 (63 probes)	API key header	Plan dependent	1251 ms
Mailjet https://api.mailjet.com/v3/REST/	up	90 (64 probes)	apiKey	6 000 emails/month, 200/day (free tier)	124 ms
Resend https://api.resend.com/emails	up	100 (88 probes)	Bearer API key	10 req/s	191 ms

Current health (latest probe) and historical reliability (score over all samples) are shown separately: a service can be up now with a weak history, or the reverse.

Try it in your agent

100 calls/day without a key, 1,000/day with a free key. MCP endpoint: https://agentnexus.app/mcp

Get a free key Connect your agent