# Platform capabilities (public)

> Markdown version of https://docs.postlake.dev/api/get-platforms . The canonical page for humans.
> PostLake is the social media API for AI agents: https://postlake.dev/llms.txt

`GET /v1/platforms`

Machine-readable capabilities per platform: character limits, media rules (required / video-only / max images / formats / sizes), whether publishing is asynchronous, and every platformOptions field with its valid values. No authentication required.

## Request

Authenticate with a bearer API key. Agents calling over MCP authorise with OAuth instead and never handle the key.

```bash
curl -X GET https://api.postlake.dev/v1/platforms \
  -H "Authorization: Bearer $POSTLAKE_API_KEY"
```


## Response

Success (`200`).

| Field | Type | Required | What it is |
| --- | --- | --- | --- |
| `platforms` | array | Yes |  |



### Example

```json
{
  "platforms": [
    "…"
  ]
}
```


## Calling this from an agent

Agents do not call REST. They call tools. Over the hosted MCP server this operation is `get_platform_capabilities`, and the agent authorises with OAuth so your API key is never pasted into a chat or seen by the model. You control what any one agent may do: which brands it may act for, which networks it may reach, how much a day, and whether it may spend credits bought up front.

## Errors

Every failure uses one shape: a stable `type`, a granular `code`, the field at fault in `param`, and a plain-language `fix`. See https://docs.postlake.dev/errors.md .

Retries are safe: send the same `Idempotency-Key` and a call that already succeeded returns its original result rather than repeating it.

## Common questions

**Can an AI agent do this without the REST API?**

Yes. Over MCP the same job is the get_platform_capabilities tool. The agent authorises with OAuth, so no API key is pasted into a chat or seen by the model, and the answer comes back in the same normalised shape.

**How often can I call this?**

Reads are rate limited per account and every response carries X-RateLimit-Remaining and X-RateLimit-Reset. On a 429 the Retry-After header tells you how long to wait.

**What happens when it fails?**

You get one error shape: a stable type, a granular code you can branch on, the offending field in param, and a fix written so an agent can correct itself rather than stop. Full list on Errors and retries.

## Related

- [One platform's capabilities (public)](https://docs.postlake.dev/api/get-platforms-by-platform.md) `GET /v1/platforms/{platform}`