Neynar Documentation

The Tier Registry allows Farcaster accounts to purchase or extend Farcaster Pro subscriptions. Unlike other protocol contracts, the Tier Registry is deployed on Base Mainnet. If you want to purchase a Pro subscription for a Farcaster account, use the Tier Registry.

Active Tiers

Tier ID	Description	Payment Token	Min Days	Price/day
1	Farcaster Pro	USDC	30	`328767` wei USDC

Read

price

Get the total price in payment token (uint256) to purchase a tier subscription for a given number of days.

Param Name	type	Description
tier	`uint256`	The tier ID to calculate price for
forDays	`uint256`	The number of days to calculate price for

tierInfo

Get information about a specific tier. Returns a TierInfo struct.

Param Name	type	Description
tier	`uint256`	The tier ID

TierInfo struct parameters:

Param Name	type	Description
minDays	`uint256`	Minimum number of days required to purchase
maxDays	`uint256`	Maximum number of days per purchase
vault	`address`	Payment destination address
paymentToken	`IERC20`	ERC20 payment token
tokenPricePerDay	`uint256`	Price per day in fundamental units of `paymentToken`
isActive	`bool`	Whether tier is currently active

Write

purchaseTier

Purchase a subscription tier for a given fid. If the account already has an active subscription, purchasing will extend their total subscription time.

Param Name	type	Description
fid	`uint256`	The fid to credit the subscription to
tier	`uint256`	The tier ID to calculate price for
forDays	`uint256`	The number of days to calculate price for

batchPurchaseTier

Purchase a subscription tier for multiple fids in a single transaction. If an account already has an active subscription, purchasing will extend their total subscription time.

Param Name	type	Description
tier	`uint256`	The tier ID to calculate price for
fids	`uint256[]`	Array of fids
forDays	`uint256[]`	Array of days, corresponding to each fid in the `fids` array

Events

PurchasedTier

Emitted when a tier is purchased for a Farcaster account.

Param Name	type	Description
fid	`uint256 indexed`	Farcaster ID the tier was purchased for
tier	`uint256 indexed`	Tier ID that was purchased
forDays	`uint256`	Number of days of subscription purchased
payer	`address indexed`	Caller address that paid

Errors

Error	Selector	Description
InvalidDuration	`76166401`	The caller attempted to purchase an invalid number of days.
InvalidTier	`e1423617`	The caller attempted to purchase an invalid or inactive tier.
InvalidBatchInput	`0a514b99`	The caller provided mismatched arrays of `fids` and `forDays`.

Source

TierRegistry.sol

Overview

Learn

Developers

AuthKit

Reference

Tier Registry

Active Tiers

Read

price

tierInfo

Write

purchaseTier

batchPurchaseTier

Events

PurchasedTier

Errors

Source

​Active Tiers

​Read

​price

​tierInfo

​Write

​purchaseTier

​batchPurchaseTier

​Events

​PurchasedTier

​Errors

​Source

Active Tiers

Read

price

tierInfo

Write

purchaseTier

batchPurchaseTier

Events

PurchasedTier

Errors

Source