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

# Introduction

> What the Alterscope Developer API is, who it's for, and the shape of every response.

The Alterscope Developer API delivers institutional DeFi risk data through one HTTP API: oracle classification and per-block price history, vault liquidity and exit simulation, curator track records, cross-protocol exposure, and a knowledge-graph view of how risk spreads between protocols. Every response also carries a machine-readable freshness and quality signal, so an automated consumer can tell how much to trust a number before acting on it.

This section gets you from zero to your first authenticated call. If you're evaluating the data or methodology rather than integrating, start with [Why Alterscope](/overview) and [Trust & Methodology](/trust/methodology/overview) instead.

<CardGroup cols={2}>
  <Card title="Get an API key" icon="key" href="https://app.alterscope.org/connections">
    Free tier in about a minute. No credit card.
  </Card>

  <Card title="Quickstart" icon="rocket" href="/develop/get-started/quickstart">
    Make your first authenticated request in \~5 minutes.
  </Card>

  <Card title="Authentication" icon="lock" href="/develop/get-started/authentication">
    API keys, headers, rotation, and revocation.
  </Card>

  <Card title="API reference" icon="code" href="/api-reference/overview">
    Every endpoint, request shape, and response field.
  </Card>
</CardGroup>

## Base URL

<Snippet file="base-url.mdx" />

## How a response is shaped

Every endpoint returns a JSON envelope with two top-level keys: `data` (the result) and `meta` (request metadata). On `/v2/*` endpoints, `meta._agentic` carries the freshness and quality signal, and the same information is mirrored in the `X-Schema-Version` and `X-Quality-Gate` response headers.

```json theme={null}
{
  "data": { "...": "endpoint result" },
  "meta": {
    "request_id": "req_…",
    "_agentic": {
      "freshness": { "status": "fresh" },
      "quality_gate": { "verdict": "pass" }
    }
  }
}
```

The freshness status and quality gate are first-class fields — your client can branch on them rather than guessing whether a number is current. The full contract, every field, and the exact enum values are documented in [Concepts → Response envelope](/develop/concepts/response-envelope) and [Freshness & staleness](/develop/concepts/freshness-and-staleness).

## Authentication at a glance

Requests authenticate with an API key (prefixed `sk_live_`) passed as a bearer token:

<Snippet file="auth-header.mdx" />

See [Authentication](/develop/get-started/authentication) for key rotation and revocation, and [Scopes](/develop/get-started/scopes) for what each key can access.

## Where to go next

* **[Quickstart](/develop/get-started/quickstart)** — your first call.
* **[Scopes](/develop/get-started/scopes)** — the permissions a key can hold.
* **[Rate limits](/develop/get-started/rate-limits)** — per-tier request and quota limits.
* **[Errors](/develop/get-started/errors)** — the error envelope and how to handle each status.
* **[Glossary](/develop/concepts/glossary)** — definitions for any unfamiliar term used here.