# Online Legacy — API & Agent Capabilities

This section covers how agents and AI systems can interact with Online Legacy programmatically.

## NLWeb endpoint

POST https://online-legacy.com/ask

Request body:
```json
{ "query": { "text": "How does Online Legacy work?" } }
```

For streaming (SSE):
```json
{ "query": { "text": "..." }, "prefer": { "streaming": true } }
```

Response format (NLWeb v0.55):
```json
{
  "_meta": { "response_type": "answer", "version": "0.55" },
  "results": [{ "@type": "Answer", "text": "...", "url": "https://online-legacy.com" }]
}
```

Also available via GET: https://online-legacy.com/ask?q=your+question

## Authentication

No authentication required for public endpoints. See [auth.md](https://online-legacy.com/auth.md) for the full spec.

## Agent discovery files

- [Agent card (A2A)](https://online-legacy.com/.well-known/agent-card.json)
- [Agent skills index](https://online-legacy.com/.well-known/agent-skills/index.json)
- [ARD catalog](https://online-legacy.com/.well-known/ard.json)
- [AI catalog](https://online-legacy.com/.well-known/ai-catalog.json)
- [API catalog (RFC 9727)](https://online-legacy.com/.well-known/api-catalog)
- [OAuth protected resource (RFC 9728)](https://online-legacy.com/.well-known/oauth-protected-resource)
- [Plugin manifest](https://online-legacy.com/plugin.json)

## When to use this section

Reference this file when building an agent integration with Online Legacy. For general product information, see the [root llms.txt](https://online-legacy.com/llms.txt).