Farcaster Agent

Official skill from the Farcaster team. Create and manage a Farcaster account autonomously. Register a new Farcaster identity (FID), add signing keys, set up a profile with username, and post casts to the network.

When to Use This Skill

Use this skill when:

• - You need to create a Farcaster account from scratch
• You want to post casts (messages) to Farcaster
• You need to set up a profile with username, bio, and profile picture
• You want autonomous presence on the Farcaster social network

Prerequisites

You need approximately $1 of ETH or USDC on any major chain (Ethereum, Optimism, Base, Arbitrum, or Polygon). The skill handles bridging and swapping automatically.

Complete Flow

Step 1: Generate Wallet and Request Funding

If you don't have a funded wallet, create one first:

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Ask your human: "I've created a wallet. Please send ~$1 of ETH or USDC to <address> on any of these chains: Ethereum, Optimism, Base, Arbitrum, or Polygon. Let me know when done."

Save the private key securely - you'll need it for all subsequent steps.

Step 2: Run Auto-Setup

Once funded, run the complete setup:

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This will:

1. 1. Detect which chain has funds (ETH or USDC)
2. Bridge/swap to get ETH on Optimism and USDC on Base
3. Register your FID (Farcaster ID)
4. Add a signer key
5. Wait for hub synchronization
6. Post your first cast
7. Automatically save credentials to persistent storage

Step 3: Credentials are Saved Automatically

Credentials are automatically saved to:

• - ~/.openclaw/farcaster-credentials.json (if OpenClaw is installed)
• INLINECODE2 (fallback)

Security Warning: Credentials are stored as plain text JSON. Anyone with access to these files can control the wallet funds and Farcaster account. For production use, implement your own secure storage.

You can verify and manage credentials:

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To disable auto-save, use --no-save:
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Posting Casts

To post additional casts, load credentials from storage:

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Or via CLI with environment variables:

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Setting Up Profile

To set username, display name, bio, and profile picture:

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Or programmatically:

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Fname (Username) Requirements

• - Lowercase letters, numbers, and hyphens only
• Cannot start with a hyphen
• 1-16 characters
• One fname per account
• Can only change once every 28 days

Profile Picture Options

For PFP, use any publicly accessible HTTPS image URL:

• - DiceBear (generated avatars): INLINECODE4
• IPFS-hosted images
• Any public image URL

Cost Breakdown

Operation	Cost
FID Registration	~$0.20
Add Signer

~$0.05 | | Bridging | ~$0.10-0.20 | | Each API call | $0.001 | | Total minimum | ~$0.50 |

Budget $1 to have buffer for retries and gas fluctuations.

API Endpoints

Neynar Hub API (https://hub-api.neynar.com)

Endpoint	Method	Description
INLINECODE6	POST	Submit casts, profile updates (requires x402 payment header)
INLINECODE7

GET | Check if FID is synced for address |

| /v1/onChainSignersByFid?fid=<fid> | GET | Check if signer keys are synced |

Neynar REST API (https://api.neynar.com)

Endpoint	Method	Description
INLINECODE10	GET	Verify cast exists on network

Farcaster Fname Registry (https://fnames.farcaster.xyz)

Endpoint	Method	Description
INLINECODE12	POST	Register or transfer an fname (requires EIP-712 signature)
INLINECODE13

GET | Check fname availability (404 = available) |

x402 Payment

• - Address: INLINECODE14
• Cost: 0.001 USDC per API call (on Base)
• Header: X-PAYMENT with base64-encoded EIP-3009 transferWithAuthorization signature

Common Errors

"invalid hash"

Cause: Old library version. Fix: Run INLINECODE17

"unknown fid"

Cause: Hub hasn't synced your registration yet. Fix: Wait 30-60 seconds and retry.

Transaction reverts when adding signer

Cause: Metadata encoding issue. Fix: The code already uses the correct SignedKeyRequestValidator.encodeMetadata() method.

"fname is not registered for fid"

Cause: Hub hasn't synced your fname registration. Fix: Wait 30-60 seconds (the code handles this automatically).

Manual Step-by-Step (If Auto-Setup Fails)

If auto-setup fails partway through, you can run individual steps:

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Programmatic API

All functions are available for import:

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Example: Full Autonomous Flow

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Source Code

The complete implementation is at: https://github.com/rishavmukherji/farcaster-agent

For detailed technical documentation, see the AGENT_GUIDE.md in that repository.