# Applications

> Name the applications that use the gateway, attribute their traffic through their keys, and control what they send to Langfuse.

Product: AI Cost Optimizer Gateway (ACOG). Web version: https://tessarac.com/docs/acog/administer/applications. Last updated: 2026-10-16.

An application is a name for the traffic one of your systems sends through ACOG, such as `support-bot` or `nightly-etl`. Reports, rate limits, DLP policy rules and traces can then be broken down or set per application.

Open **Admin → Applications**. You need the **Create and revoke API keys for anyone in the org** permission (`admin:keys`).

## How traffic is attributed

Every request is attributed to the application that owns the service key it was made with. No request header can change the attribution, so callers cannot report their traffic as another application's. Requests from keys with no application, including all user keys, are reported as `unattributed`.

## Registering an application

| Field | Notes |
|---|---|
| Name | A display name |
| Slug | Lowercase letters, digits and hyphens. Permanent: it names the application on every trace. `acog` is reserved. |
| Forward traces | On by default. When on, ACOG sends a trace to Langfuse for every request the application makes (if Langfuse is configured). Turn it off for an application that already sends its own traces. Usage, cost and savings reporting are unaffected either way. |
| Trace tags, trace filter | Tags added to this application's traces, and sampling. See [Observability](https://tessarac.com/docs/acog/administer/observability.md). |

Then assign service keys to it on the **Developer** page.

## Deleting an application

Its keys keep working: they are unbound, not disabled, and their traffic goes back to being reported as `unattributed`.