docs: expand remote.http documentation to demonstrate target label op…

…tions (#5233)

CHANGELOG.md

@@ -103,6 +103,7 @@ Main (unreleased)
   have been standardized. The first fields will always be `ts`, `level`, and
   `msg`, followed by non-common fields. Previously, the position of `msg` was
   not consistent. (@rfratto)
+- Documentation updated to link discovery.http and prometheus.scrape advanced configs (@proffalken)
 
 ### Bugfixes
 

docs/sources/flow/reference/components/discovery.http.md

@@ -27,6 +27,53 @@ Example response body:
 ]
 ```
 
+It is possible to use additional fields in the JSON to pass parameters to [prometheus.scrape](../prometheus.scrape#technical-details) such as the `metricsPath` and `scrape_interval`.
+
+As an example, the following will provide a target with a custom `metricsPath`, scrape interval, and timeout value:
+
+```json
+[
+   {
+      "labels" : {
+         "__metrics_path__" : "/api/prometheus",
+         "__scheme__" : "https",
+         "__scrape_interval__" : "60s",
+         "__scrape_timeout__" : "10s",
+         "service" : "custom-api-service"
+      },
+      "targets" : [
+         "custom-api:443"
+      ]
+   },
+]
+
+```
+
+It is also possible to append query parameters to the metrics path with the `__param_<name>` syntax.
+
+For example, the following will call a metrics path of `/health?target_data=prometheus`:
+
+```json
+[
+   {
+      "labels" : {
+         "__metrics_path__" : "/health",
+         "__scheme__" : "https",
+         "__scrape_interval__" : "60s",
+         "__scrape_timeout__" : "10s",
+         "__param_target_data": "prometheus",
+         "service" : "custom-api-service"
+      },
+      "targets" : [
+         "custom-api:443"
+      ]
+   },
+]
+
+```
+
+For more information on the potential labels you can use, see the [prometheus.scrape technical details](../prometheus.scrape#technical-details) section, or the [Prometheus Configuration](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#relabel_config) documentation.
+
 ## Usage
 
 ```river