TLS_CREDENTIAL_CA_CERTIFICATE problem to understand.

[CreativeIndustryAg]

Hello
i'm working witch echo_clinet example with TLS config, also i'm not experienced in cryptography.
That's why i'm asking you for help.

static const unsigned char ca_certificate[] = { #include "echo-apps-cert.der.inc" };

`int err = tls_credential_add(CA_CERTIFICATE_TAG,

			    TLS_CREDENTIAL_CA_CERTIFICATE,
			    ca_certificate, //ca_certificate is just a client certificate.
			    sizeof(ca_certificate));
if (err < 0) {
	LOG_ERR("Failed to register public certificate: %d", err);
}`

My question is: why is a public certificate assigned to config TLS_CREDENTIAL_CA_CERTIFICATE?
I think: According to the name of this config, a CA certificate should be assigned.

Ofc in documentation there is information https://docs.zephyrproject.org/apidoc/latest/group__tls__credentials.html
" TLS_CREDENTIAL_CA_CERTIFICATE: A trusted CA certificate. Use this to authenticate remote servers. Used with certificate-based ciphersuites."

Is that just a bad config name? do I get something wrong?