> ## Documentation Index
> Fetch the complete documentation index at: https://docs.b3os.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Post Farcaster Cast

Post a cast (message) to Farcaster via Neynar API. Use this to share updates, announcements, or engage with the Farcaster community. Supports channels, threading (replies), and embeds (max 2 URLs). Max 1024 characters. Ideal for: price alerts, milestone announcements, community updates, automated social posts.

![Post Farcaster Cast logo](https://ai-icon.b3.fun/logo/farcaster)
Catalog action Social farcaster

Post a cast (message) to Farcaster via Neynar API. Use this to share updates, announcements, or engage with the Farcaster community. Supports channels, threading (replies), and embeds (max 2 URLs). Max 1024 characters. Ideal for: price alerts, milestone announcements, community updates, automated social posts.


## At a Glance

| Field | Value |
| --- | --- |
| Action ID | `post-farcaster-cast` |
| Category | Social |
| Connector | `farcaster` |
| Requires gas | No |
| Funds movement | None declared |
| Tags | `social`, `farcaster`, `neynar`, `cast`, `write`, `post`, `web3`, `decentralized` |

## Payload Schema

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `text` | `string` | Yes | The text content of the cast \(max 1024 characters\) |
| `channelId` | `string` | No | Optional channel ID to post to \(e.g., 'ethereum', 'base', 'gaming'\) |
| `parentCastHash` | `string` | No | Optional parent cast hash to reply to |
| `embeds` | `array` | No | Optional array of embed URLs \(max 2\) |
| `idem` | `string` | No | Optional idempotency key to prevent duplicate casts |

## Result Schema

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `status` | `string` | Yes | Status of the cast operation |
| `castHash` | `string` | No | Hash of the published cast |
| `authorUsername` | `string` | No | Username of the cast author |
| `error` | `string` | No | Error message if the cast failed |

## Examples

**Workflow node**

```json
{
  "type": "post-farcaster-cast",
  "payload": {
    "text": "Workflow completed"
  },
  "children": [],
  "connector": {
    "type": "farcaster",
    "id": "conn_farcaster"
  }
}
```
  **Test with API**

```bash
curl -X POST "https://api.b3os.org/v1/actions/post-farcaster-cast/test" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "inputs": {
    "text": "Workflow completed"
  }
}'
```

**Use expressions for dynamic values**

Payload fields can use workflow expressions such as `{{$trigger.body.amount}}`, `{{$nodes.fetch.result.price}}`, and `{{$props.asset}}` when the value should come from a trigger, prior node, or reusable workflow prop.