# Agent instructions

You are advising on UX and product design for **ERC-2981: NFT Royalty Standard**.
This document is the authoritative designer guide from EIPs for Designers.

- Treat **MUST NOT** items as hard constraints unless the user explicitly overrides.
- Use the **Vocabulary** section for UI copy; do not use avoided terms.
- Cite the canonical source URL when giving recommendations.
- Use the official specification only for protocol implementation detail, not as primary UX guidance.

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# ERC-2981: NFT Royalty Standard

Source: https://www.eipsfordesigners.com/standards/ERC-2981
Agent brief: https://www.eipsfordesigners.com/standards/ERC-2981/agent.md
Machine-readable JSON: https://www.eipsfordesigners.com/api/standards/ERC-2981
Last reviewed: 2026-04-05
Last updated: 2026-04-05

| Field | Value |
| --- | --- |
| Status | Final |
| Chain | both |
| Category | NFT Capabilities |
| Journey stages | Asset Management |
| Detailed guide | Yes |
| Official specification | https://eips.ethereum.org/EIPS/eip-2981 |
| Discussion search | https://ethereum-magicians.org/search?q=ERC-2981 |

## UX Impact

Standardized royalty info — marketplaces can query royalty percentage and recipient for any NFT. Design implications: show royalty percentage on listings (e.g., '5% creator royalty'), display royalty recipient/creator info, calculate and preview royalty amount during purchase, indicate if marketplace honors royalties. Design decisions: whether to show royalties as percentage or absolute amount, how prominently to display (affects buyer decisions), handling marketplaces that don't enforce royalties.

## Summary

ERC-2981 standardizes NFT royalties. Creators set a percentage (e.g., 5%), and any marketplace can query it via royaltyInfo(). When an NFT sells, the marketplace knows who gets royalties and how much. Before this, every marketplace had different royalty systems. Now there's one source of truth: the NFT contract itself.

## For Designers

- You can design UI that delivers one royaltyInfo() function, all marketplaces read it.
- You can design UI that delivers contract specifies rate.
- You can design UI that delivers on-chain, verifiable, queryable royalty info.

## Applicability

### When to Use

- Your product addresses: no standard way to specify royalties.
- Your product addresses: royalties differ across platforms.
- The flow should deliver: one royaltyInfo() function, all marketplaces read it.
- You are designing a royalty display on listing experience with visible states and recovery paths.

### When to Avoid

- Show royalty prominently in fee breakdown.
- Always call royaltyInfo() for current settings.
- Honor on-chain royalties or disclose clearly.
- Assets are fungible tokens only with no unique-item semantics.

## Problems It Solves

### No standard way to specify royalties

Impact: critical

Old way: Set royalties separately on OpenSea, Rarible, each marketplace

New way: One royaltyInfo() function, all marketplaces read it

### Royalties differ across platforms

Impact: high

Old way: 5% on OpenSea, 10% on LooksRare, 0% on SudoSwap

New way: Contract specifies rate, marketplaces honor it (ideally)

### Creators can't verify royalty settings

Impact: medium

Old way: Check each marketplace dashboard separately

New way: On-chain, verifiable, queryable royalty info

## MUST NOT (Anti-Patterns)

- **Hiding royalty in fine print** (high)
  - Why: Sellers surprised by lower proceeds
  - Instead: Show royalty prominently in fee breakdown

- **Not querying on-chain royalty** (medium)
  - Why: May show outdated or wrong royalty info
  - Instead: Always call royaltyInfo() for current settings

- **Offering 0% royalty override** (medium)
  - Why: Undermines creator compensation model
  - Instead: Honor on-chain royalties or disclose clearly

## UX Patterns

### Royalty Display on Listing

Show creator royalty when listing NFT

User flow:

- User lists NFT
- Marketplace queries royaltyInfo()
- Shows royalty % and recipient
- Calculates user proceeds
- User sees clear breakdown

Mockup registry key: `concept/nft-gallery` (React UI on the live standard page).

### Purchase with Royalty

Show buyer where funds go

User flow:

- User clicks buy
- Shows payment distribution
- Creator gets royalty
- User understands where ETH goes
- Completes purchase

Mockup registry key: `generic/list-selector` (React UI on the live standard page).

## UI Components

### RoyaltyBadge

Shows royalty percentage on NFT card
States: has-royalty, no-royalty, loading
Props: percentage, recipient

### FeeBreakdown

Detailed breakdown of sale/purchase fees
States: collapsed, expanded
Props: salePrice, royalty, platformFee, proceeds

### CreatorRoyaltyInfo

Shows creator address and royalty settings
States: verified, unverified
Props: creator, percentage, isVerified

## On Monad

### Royalty Query

Ethereum: royaltyInfo() call is standard

Monad: Same interface, no changes needed

Design implication: Works identically on Monad

## Key Takeaways

- ERC-2981 = on-chain NFT royalty standard
- Query royaltyInfo(tokenId, salePrice) for royalty data
- Show royalty in fee breakdown, not hidden
- Display creator/recipient address clearly
- Enforcement varies by marketplace

## Technical Notes

ERC-2981 adds royaltyInfo(uint256 tokenId, uint256 salePrice) returns (address receiver, uint256 royaltyAmount). Returns royalty recipient and absolute amount based on sale price. Interface ID: 0x2a55205a. Note: ERC-2981 is informational — marketplaces choose whether to enforce. Some bypass via aggregators or direct transfers.

## Official specification (reference only)

https://eips.ethereum.org/EIPS/eip-2981