# User agent
- [User-agent Attributes](#user-agent-attributes)
- [User-agent OS Attributes](#user-agent-os-attributes)
## User-agent Attributes
Describes user-agent attributes.
| Attribute | Type | Description | Examples | Stability |
|---|---|---|---|---|
| `user_agent.name` | string | Name of the user-agent extracted from original. Usually refers to the browser's name. [1] | `Safari`; `YourApp` |  |
| `user_agent.original` | string | Value of the [HTTP User-Agent](https://www.rfc-editor.org/rfc/rfc9110.html#field.user-agent) header sent by the client. | `CERN-LineMode/2.15 libwww/2.17b3`; `Mozilla/5.0 (iPhone; CPU iPhone OS 14_7_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.1.2 Mobile/15E148 Safari/604.1`; `YourApp/1.0.0 grpc-java-okhttp/1.27.2` |  |
| `user_agent.version` | string | Version of the user-agent extracted from original. Usually refers to the browser's version [2] | `14.1.2`; `1.0.0` |  |
**[1] `user_agent.name`:** [Example](https://www.whatsmyua.info) of extracting browser's name from original string. In the case of using a user-agent for non-browser products, such as microservices with multiple names/versions inside the `user_agent.original`, the most significant name SHOULD be selected. In such a scenario it should align with `user_agent.version`
**[2] `user_agent.version`:** [Example](https://www.whatsmyua.info) of extracting browser's version from original string. In the case of using a user-agent for non-browser products, such as microservices with multiple names/versions inside the `user_agent.original`, the most significant version SHOULD be selected. In such a scenario it should align with `user_agent.name`
## User-agent OS Attributes
Describes the OS user-agent attributes.
| Attribute | Type | Description | Examples | Stability |
|---|---|---|---|---|
| `user_agent.os.name` | string | Human readable operating system name. [3] | `iOS`; `Android`; `Ubuntu` |  |
| `user_agent.os.version` | string | The version string of the operating system as defined in [Version Attributes](/docs/resource/README.md#version-attributes). [4] | `14.2.1`; `18.04.1` |  |
| `user_agent.synthetic.type` | string | Specifies the category of synthetic traffic, such as tests or bots. [5] | `bot`; `test` |  |
**[3] `user_agent.os.name`:** For mapping user agent strings to OS names, libraries such as [ua-parser](https://github.com/ua-parser) can be utilized.
**[4] `user_agent.os.version`:** For mapping user agent strings to OS versions, libraries such as [ua-parser](https://github.com/ua-parser) can be utilized.
**[5] `user_agent.synthetic.type`:** This attribute MAY be derived from the contents of the `user_agent.original` attribute. Components that populate the attribute are responsible for determining what they consider to be synthetic bot or test traffic. This attribute can either be set for self-identification purposes, or on telemetry detected to be generated as a result of a synthetic request. This attribute is useful for distinguishing between genuine client traffic and synthetic traffic generated by bots or tests.
---
`user_agent.synthetic.type` has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.
| Value | Description | Stability |
|---|---|---|
| `bot` | Bot source. |  |
| `test` | Synthetic test source. |  |