---
title: Dependencies
description: APM agents collect details about external calls made from instrumented services. Sometimes, these external calls resolve into a downstream service that’s...
url: https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/1655/solutions/observability/apm/dependencies
products:
  - APM
  - Elastic Cloud Serverless
  - Elastic Observability
---

# Dependencies
APM agents collect details about external calls made from instrumented services. Sometimes, these external calls resolve into a downstream service that’s instrumented — in these cases, you can utilize [distributed tracing](/elastic/docs-content/pull/1655/solutions/observability/apm/trace-sample-timeline#distributed-tracing) to drill down into problematic downstream services. Other times, though, it’s not possible to instrument a downstream dependency — like with a database or third-party service. **Dependencies** gives you a window into these uninstrumented, downstream dependencies.
![Dependencies view in the Applications UI](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/1655/solutions/images/observability-dependencies.png)

Many application issues are caused by slow or unresponsive downstream dependencies. And because a single, slow dependency can significantly impact the end-user experience, it’s important to be able to quickly identify these problems and determine the root cause.
Select a dependency to see detailed latency, throughput, and failed transaction rate metrics.
![Dependencies drilldown view in the Applications UI](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/1655/solutions/images/observability-dependencies-drilldown.png)

When viewing a dependency, consider your pattern of usage with that dependency. If your usage pattern *hasn’t* increased or decreased, but the experience has been negatively affected—either with an increase in latency or errors—there’s likely a problem with the dependency that needs to be addressed.
If your usage pattern *has* changed, the dependency view can quickly show you whether that pattern change exists in all upstream services, or just a subset of your services. You might then start digging into traces coming from impacted services to determine why that pattern change has occurred.

## Operations

<::::{Warning}>
  The Dependency operations functionality is in beta and is subject to change. The design and code is less mature than official generally available features and is being provided as-is with no warranties.
</::::{Warning}>

**Dependency operations** provides a granular breakdown of the operations/queries a dependency is executing.
![operations view in the Applications UI](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/1655/solutions/images/observability-operations.png)

Selecting an operation displays the operation’s impact and performance trends over time, via key metrics like latency, throughput, and failed transaction rate. In addition, the [**Trace sample timeline**](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/1655/solutions/observability/apm/trace-sample-timeline) provides a visual drill-down into an end-to-end trace sample.
![operations detail view in the Applications UI](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/1655/solutions/images/observability-operations-detail.png)