The header name is [ASCII case-insensitive](https://infra.spec.whatwg.org/#ascii-case-insensitive). That is, `TRACERESPONSE`, `TraceResponse`, and `traceresponse` are ...
Should be human readable. Cryptic header will hide the fact of potential information disclosure. Should be appende-able (comma-separated) https://tools.ietf.org/html ...