Honeycomb's API lives at https://api.honeycomb.io/1 (api.eu1.honeycomb.io for EU).
Create an API key in your environment's settings and send it as the X-Honeycomb-Team header. In the examples it's written {{HONEYCOMB_API_KEY}}.
Full reference: https://api-docs.honeycomb.io/
Which team and environment the key belongs to, and what it can do.
curl https://api.honeycomb.io/1/auth \
-H "X-Honeycomb-Team: {{HONEYCOMB_API_KEY}}"
curl https://api.honeycomb.io/1/datasets \
-H "X-Honeycomb-Team: {{HONEYCOMB_API_KEY}}"
curl -X POST https://api.honeycomb.io/1/events/{{DATASET}} \
-H "X-Honeycomb-Team: {{HONEYCOMB_API_KEY}}" \
-H "Content-Type: application/json" \
-d '{"endpoint": "/checkout", "duration_ms": 153}'