> ## Documentation Index
> Fetch the complete documentation index at: https://docs.subtrace.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Tags

> Set tags on requests to categorize them and search faster

You can configure Subtrace to tag requests to categorize and search faster when
you're dealing with large request volumes. For instance, if you have a
microservice architecture, it's useful to tag each request by the service name
so that you can filter requests by service later. Here's an example config:

```yaml theme={null}
tags:
  service_name: payments-api
  deploy_env: prod
  has_gpu: false
```

Use the `--config` command line flag to pass the config file to Subtrace:

```bash theme={null}
subtrace run --config=/path/to/subtrace.yaml -- node app.js
```

## Default Tags

Subtrace automatically populates requests with the following set of default set
of tags based on the information it can gather about the environment:

* `hostname`

The following default tags may be relevant if you're on Google Cloud:

* `gcp_project`
* `gke_cluster_location`
* `gke_cluster_name`
* `gke_node_name`