CREDENTIAL_REQUIRED
This deployment requires a credential on every call and none was presented. HTTP 401. Obtain an evaluation credential with one POST, no sign-up, and retry.
The hosted service requires the x-jaxon-credential header on every scoped call, and the request had none. The remedy needs no person.
The envelope
{"ok": false,
"error": {"code": "CREDENTIAL_REQUIRED",
"message": "this deployment requires a credential on every call. Obtain an evaluation credential automatically with POST /v1/credentials/evaluation (no sign-up), then send it as the x-jaxon-credential header.",
"docs": "https://docs.agents.jaxon.ai/errors/credential-required.md"},
"versions": {"...": "..."}}
The fix, without a human
curl -s -X POST https://agents.jaxon.ai/v1/credentials/evaluation
# -> {"ok": true, "credential": "<token, shown once>", "grade": "evaluation", ...}
Store the credential value (the service keeps only its hash and cannot show it again) and send it as x-jaxon-credential on every call. The dsail Python client does exactly this on a 401 โ obtains, stores at ~/.config/dsail/credential, retries once.
What an evaluation credential can do
Compile, check and fetch the prompt pack, capped per day and over its lifetime, and it expires. Storage operations โ saving a ruleset under a name, recording an approval, adding a converter โ need a full credential, issued by Jaxon; asking with an evaluation credential answers [CREDENTIAL_SCOPE](credential-scope.md).
The MCP door used by claude.ai and ChatGPT authenticates with OAuth instead and never sees this code.
See also: Quickstart: REST, Error codes.