Tracestate
Both directions
Carries vendor-specific trace data alongside traceparent.
| On the wire | Tracestate: … |
|---|---|
| Category | Both directions |
Headers that can appear on either side.
How to read this
- The first digit of a status code carries the meaning: 4 means the request, 5 means the server.
- 404 means "not there"; 403 means "there, but not for you". Swapping them makes debugging slower.
- Header names are case-insensitive — Content-Type and content-type are the same header.
- Caching and CORS problems usually come down to one header line, visible in the browser’s network tab.
Frequently asked questions
Q. What does HTTP Tracestate mean?
Carries vendor-specific trace data alongside traceparent.
Q. What does Tracestate look like on the wire?
It travels as Tracestate: …
Q. Where does Tracestate appear?
In both directions.
Q. What group does Tracestate belong to?
The both directions group; the rest of that group is listed further down.