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

# Core concepts

> The building blocks of Valkyrie: deployments, fine-tuning jobs, GPUs, the wallet, aliases, and the MCP server.

A short tour of the objects you'll work with in Valkyrie and how they relate.

## Models, deployments, and jobs

<CardGroup cols={2}>
  <Card title="Fine-tuning job" icon="graduation-cap">
    A training run that adapts an open base model to your dataset using a managed
    Unsloth pipeline. Produces model outputs (weights/adapters) stored for you.
  </Card>

  <Card title="Deployment" icon="server">
    A running, servable model behind an OpenAI-compatible endpoint. It can serve a
    fine-tuned model or any Hugging Face base model, using vLLM or Ollama.
  </Card>
</CardGroup>

A typical lifecycle is **dataset → fine-tuning job → deployment → API calls**, but
you can skip straight to a deployment if you just want to serve an existing model.

## GPUs are provisioned on demand

Valkyrie doesn't keep idle GPUs around. When you launch a job or a deployment, it
provisions a GPU from a cloud marketplace, runs your workload, and releases it when
it's no longer needed. Deployments can auto-stop when idle and be resumed on demand,
so you pay for compute you actually use.

<Note>
  You never manage GPU machines, drivers, or serving infrastructure yourself.
  Valkyrie handles provisioning, setup, health monitoring, and teardown.
</Note>

## The wallet

Billing is **prepaid and per-use**. You add credit to a wallet, and jobs and
deployments draw against it. Your balance is computed from the full ledger of
credits and debits, so every charge and top-up is auditable. See
[Quota & billing](/guides/wallet-billing).

## Aliases

An **alias** is a stable, human-readable name for a deployment. Instead of calling a
raw deployment slug, you call:

```
/{account_slug}/{alias}/v1/chat/completions
```

Aliases let you swap the underlying deployment (for example, after redeploying a new
version) without changing the URL your applications use. See [Aliases](/guides/aliases).

## Ways to use Valkyrie

<CardGroup cols={3}>
  <Card title="Dashboard" icon="table-columns" href="/dashboard/overview">
    The web app for people: manage keys, datasets, jobs, deployments, and spend.
  </Card>

  <Card title="OpenAI-compatible API" icon="code" href="/api-reference/introduction">
    Call your deployed models from any OpenAI-compatible client or SDK.
  </Card>

  <Card title="MCP server" icon="wand-magic-sparkles" href="/mcp/overview">
    Let an AI agent provision, deploy, and operate models programmatically.
  </Card>
</CardGroup>

## Authentication at a glance

| Credential       | Header                          | Used by                           |
| ---------------- | ------------------------------- | --------------------------------- |
| JWT bearer token | `Authorization: Bearer <token>` | People signed in to the dashboard |
| API key          | `X-API-Key: <key>`              | Applications, scripts, and agents |

API keys are prefixed by purpose, for example, deployment keys begin with
`vk_dep_` and MCP keys begin with `vk_mcp_`. See
[Authentication](/api-reference/authentication).