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

# KV

> Reference the KV keys that services use to publish discoverable application metadata.

This page lists the KV conventions exposed by the Kernel and core services.
Each entry defines what information a key represents and which component
currently publishes it. For KV operations and storage behavior, see the [KV
storage guide](./isc-kv).

## Kernel service records

The Kernel publishes service metadata in the read-only `sys` namespace. These
records let other components distinguish an available service package from a
service instance that has registered with the Kernel.

| Key pattern                          | Defined by | Meaning                                                                             |
| ------------------------------------ | ---------- | ----------------------------------------------------------------------------------- |
| `sys/service/catalog/<service-name>` | Kernel     | Metadata for a service package discovered during scanning.                          |
| `sys/service/<instance-id>`          | Kernel     | Metadata for a loaded service instance and the routes and transports it registered. |

The catalog record describes package metadata, including the service
identity, version, runtime type, contract version, command, package path,
and manifest metadata. It does not indicate that the service is running.

The running-instance record describes the registered instance and its
routes and transports. The Kernel removes this record when the instance
stops or is unloaded. A degraded instance can still have a record; the
record reflects the routes and transports that were registered successfully.

## Published application metadata

Services publish metadata under a namespace derived from the service that
owns the resource. The following keys are the current conventions for
resources that other services or frontend code may need to discover.

| Key                       | Defined by           | Value meaning                                                          |
| ------------------------- | -------------------- | ---------------------------------------------------------------------- |
| `web-assets/urls`         | `web-assets` service | A JSON object mapping each published web asset name to its public URL. |
| `web-assets/style`        | `web-assets` service | The public URL of the shared stylesheet.                               |
| `web-assets/color-scheme` | `web-assets` service | The public URL of the color-scheme stylesheet.                         |
| `web-assets/icon`         | `web-assets` service | The public URL prefix for shared icons.                                |
| `web-assets/culori`       | `web-assets` service | The public URL of the Culori JavaScript resource.                      |
| `web-sdk/urls`            | `web-sdk` service    | A JSON object mapping each SDK resource name to its public URL.        |
| `web-sdk/sdk`             | `web-sdk` service    | The public URL of the web SDK script.                                  |
| `web-sdk/languages`       | `web-sdk` service    | The public URL of the SDK language metadata.                           |

The aggregate `urls` keys and their corresponding individual keys describe
the same resource set. Use the aggregate key when discovering all resources;
use an individual key when a specific resource is required.