---
metadata:
  - name: generator
    content: Diplodoc Platform v5.50.6
alternate:
  - https://ydb.tech/docs/en/reference/ydb-sdk/grpc-headers.md?version=main
  - https://ydb.tech/docs/ru/reference/ydb-sdk/grpc-headers.md?version=main
sourcePath: en/core/reference/ydb-sdk/grpc-headers.md
---
> **Documentation Index:** Fetch the complete configuration index at https://ydb.tech/docs/en/llms.txt

## gRPC metadata headers

YDB uses the following gRPC metadata headers:

* gRPC headers which a client sends to YDB:
  * `x-ydb-database` - database
  * `x-ydb-auth-ticket` - auth token from a credentials provider
  * `x-ydb-sdk-build-info` - YDB SDK build info
  * `x-ydb-trace-id` - user-defined request ID. If not defined by client YDB SDK generates automatically using [UUID](https://en.wikipedia.org/wiki/UUID) format
  * `x-ydb-application-name` - optional user-defined application name
  * `x-ydb-client-capabilities` - supported client SDK capabilities (`session-balancer` and other)
  * `x-ydb-client-pid` - client application process ID
  * `traceparent` - OpenTelemetry trace ID ([specification](https://w3c.github.io/trace-context/#header-name))

* gRPC headers which YDB sends to client with responses:
  * `x-ydb-server-hints` - notifications from YDB (such as `session-close` and other)
  * `x-ydb-consumed-units` - consumed units on the current request