Register
Standard agent registration (the auth.md protocol): one POST returns an identity, and the token endpoint turns it into a bearer. No card, no console, no person yet, and $0.10 of free credit so the first real calls work. The full recipe is at https://apiforagents.dev/auth.md.
curl -X POST https://apiforagents.dev/agent/identity \
-H "Content-Type: application/json" -d '{"type": "anonymous"}'
# then exchange the identity_assertion for a bearer token
curl -X POST https://apiforagents.dev/oauth2/token \
-d "grant_type=urn:ietf:params:oauth:grant-type:jwt-bearer&assertion=$ASSERTION"200 { "registration_id": "reg_…", "identity_assertion": "<jwt>", "pre_claim_scopes": ["catalog.read"],
"claim_token": "clm_…", "post_claim_scopes": ["catalog.read", "data.run", "account.read", "account.billing"] }
200 { "access_token": "afa_…", "token_type": "Bearer", "expires_in": 86400, "scope": "catalog.read" }