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

# Cross-signal correlation

> Move across RUM, traces, logs, metrics, profiles, services, and hosts without losing time context.

Cross-signal correlation combines stable identifiers, an organization boundary, and a shared time
window. MoleSignal builds target filters on the server, eliminating manual copying of a `trace_id`,
service, host, or session id between pages.

## The correlation API

```http theme={null}
GET /api/v1/web/correlation/{from_kind}/{to_kind}
Authorization: Bearer <jwt>
```

Given a starting signal (`from_kind`) and a target signal (`to_kind`), the endpoint returns related
signals with **prefilled filters**. The server performs the cross-signal join within the active
organization and time window.

## Available workflows

* **Service graph + RED metrics** derived from traces, ready to render as a topology view
  (`GET /api/v1/traces/service_graph`).
* **Time anchor** — one click zooms and propagates the time range across all panels.
* **Investigation stack** — drill `RUM → trace → log → metric → profile` and back while each frame
  preserves investigation context.

## Related endpoints

| Endpoint                                            | Purpose                                                |
| --------------------------------------------------- | ------------------------------------------------------ |
| `GET /api/v1/web/correlation/{from_kind}/{to_kind}` | Server-side join across signals with prefilled filters |
| `GET /api/v1/web/trace/{trace_id}`                  | Full trace with all spans                              |
| `GET /api/v1/web/topology`                          | Service topology view                                  |
| `GET /api/v1/traces/service_graph`                  | Service graph + RED metrics from traces                |
| `POST /api/v1/web/investigation/blob`               | Persist an investigation stack                         |

## The investigation stack in the UI

The web shell turns correlation into a workflow:

* **⌘K command palette** — opens every stream, dashboard, alert, and saved view with one keystroke.
* **Investigation stack** (up to 6 frames) — push a frame for each drill, navigate with `⌘[` and
  `⌘]`, and pin a frame to preserve context during exploration.
* Every clickable action is keyboard-reachable.

The stack can be serialized to a short server-side investigation blob for a shareable URL. Opening
that URL still requires normal authorization for every referenced resource.