OpenSea (NFT Marketplace Data + Seaport Trades)

OpenSea is the dominant NFT marketplace. This skill queries marketplace data — listings, offers, sales / events, floor prices, drops, traits — and executes Seaport trades via the official

@opensea/cli

. For NFT metadata (name, image, traits, ownership) outside the marketplace context, use Alchemy's NFT API instead. For pure cross-chain token swaps (no marketplace context), use the

lifi

ecosystem skill.


Primary tool	`npx @opensea/cli@latest <command>` (or `npm install -g @opensea/cli` )
REST API base	`https://api.opensea.io/api/v2`
Auth	`OPENSEA_API_KEY` header — instant via `POST /api/v2/auth/keys` , or signup at the developer portal
Optional Privy	`PRIVY_APP_ID` / `PRIVY_APP_SECRET` / `PRIVY_WALLET_ID` for write / fulfillment flows
Chains	Ethereum, Base, Arbitrum, Optimism, Polygon, and more

When to use this skill

Use

opensea

when any of the following are true:

The user wants marketplace data — listings, offers, floor prices, sales history, collection stats
The user wants to buy / sell an NFT via Seaport (fulfill listing or accept offer)
The user wants to search across OpenSea (collections / NFTs / tokens / accounts)
The user wants to monitor events — sales, transfers, mints, listings, offers — for a collection or NFT
The user wants to explore drops or build a mint transaction for a SeaDrop contract
The user wants token discovery in the OpenSea-curated context (top, trending, by group)

When NOT to use this skill (handoff)

Need	Use instead
NFT metadata (name, image, traits, ownership lookup) outside a marketplace context	`alchemy-api` (NFT API) — broader coverage, fewer rate limits
Pure cross-chain token swap (no NFT marketplace need)	`lifi` (ecosystem skill) — broader bridge / DEX aggregation
Token spot prices for valuation	`alchemy-api` (Prices API)
Token metadata, search, list by chain (general)	`alchemy-api` (Token API)
Current wallet balances (token + native)	`alchemy-api` (Portfolio / Token API)
Transaction history (transfers in / out)	`alchemy-api` (Transfers API)
Live blockchain reads (block #, gas, `eth_call` )	`alchemy-cli` (live) or `alchemy-api` (JSON-RPC)
Pre-execution simulation	`alchemy-api` (Simulation API)
Account abstraction (bundlers, gas managers)	`alchemy-api`
Smart wallet / embedded wallet flows	`alchemy-api` (Wallets / Account Kit)

Scope contract

This skill covers (
scope_in
):

Marketplace data:

opensea listings best

opensea listings best-for-nft

opensea offers best-for-nft

opensea offers all

opensea collections stats

opensea collections trending

opensea collections top

opensea collections traits

Seaport trades: fulfillment data for buying (
```
opensea-fulfill-listing.sh
```
) and selling (
```
opensea-fulfill-offer.sh
```
); creating listings / offers via
```
opensea-post.sh
```
with the Seaport order structure
Events / monitoring:
```
opensea events list
```
,
```
events by-collection
```
,
```
events by-nft
```
,
```
events by-account
```
— sale / transfer / mint / listing / offer / trait_offer / collection_offer

Drops + minting:

opensea drops list

opensea drops get

opensea drops mint

Search:
```
opensea search
```
across collections / NFTs / tokens / accounts
Account utilities:
```
opensea accounts resolve
```
(ENS / username / address)

This skill does NOT cover (
scope_out
):

General NFT metadata reads (name, image, traits, ownership, contract metadata) outside the marketplace context → handoff:
```
alchemy-api
```
(NFT API). OpenSea's NFT data is marketplace-flavored and rate-limited; Alchemy's NFT API is broader and cheaper for pure metadata.
Pure cross-chain token swaps (no NFT marketplace use case) → handoff:
```
lifi
```
(ecosystem skill). OpenSea's swap aggregator works, but
```
lifi
```
covers more bridges and chains.
Token spot prices for valuation / display → handoff:
```
alchemy-api
```
(Prices API)
General token metadata, search, list → handoff:
```
alchemy-api
```
(Token API)
Wallet balances (token + native) → handoff:
```
alchemy-api
```
(Portfolio / Token API)
Transaction transfer history → handoff:
```
alchemy-api
```
(Transfers API)
Live RPC reads → handoff:
```
alchemy-cli
```
or
```
alchemy-api
```
(JSON-RPC)
Pre-execution simulation → handoff:
```
alchemy-api
```
(Simulation API)
Account abstraction → handoff:
```
alchemy-api
```
(Wallets / Bundler / Gas Manager)
Embedded / smart wallet onboarding → handoff:
```
alchemy-api
```
(Account Kit)
Signed tx submission → user wallet (or Privy if configured for OpenSea write flows)

Setup

API key is required. Get one instantly via the auth endpoint (no signup) or register at the developer portal for higher limits:

bash

# Instant key (no signup needed)
export OPENSEA_API_KEY=$(curl -s -X POST https://api.opensea.io/api/v2/auth/keys | jq -r '.api_key')

# Or set an existing key
# export OPENSEA_API_KEY="..."

Install the CLI globally (optional —

npx @opensea/cli

works without install):

bash

npm install -g @opensea/cli

For write / fulfillment flows that sign with Privy:

bash

export PRIVY_APP_ID="..."
export PRIVY_APP_SECRET="..."
export PRIVY_WALLET_ID="..."

Security: never expose
OPENSEA_API_KEY
or Privy credentials in client-side code. Server-side only.

Endpoint reference → references/marketplace.md

Marketplace queries (most-used)

Task	CLI
Best listings for a collection	`opensea listings best <slug> [--limit <n>]`
Best listing for a specific NFT	`opensea listings best-for-nft <slug> <token_id>`
Best offer for an NFT	`opensea offers best-for-nft <slug> <token_id>`
All listings on a collection	`opensea listings all <slug> [--limit <n>]`
All offers on a collection	`opensea offers all <slug> [--limit <n>]`
Trait offers	`opensea offers traits <slug> --type <type> --value <value>`
Collection stats (floor, volume)	`opensea collections stats <slug>`
Trending collections	`opensea collections trending [--timeframe <tf>] [--chains <chains>]`
Top collections by sort	`opensea collections top [--sort-by <field>] [--chains <chains>]`
Collection traits	`opensea collections traits <slug>`

Seaport trade execution

Task	Script
Get fulfillment data to buy an NFT	`opensea-fulfill-listing.sh <chain> <order_hash> <buyer>`
Get fulfillment data to sell (accept offer)	`opensea-fulfill-offer.sh <chain> <order_hash> <seller> <contract> <token_id>`
Generic POST to OpenSea API	`opensea-post.sh <path> <json_body>`

Events / monitoring

Task	CLI
Recent events (filterable by type)	`opensea events list [--event-type <type>]`
Events for a collection	`opensea events by-collection <slug> [--event-type <type>]`
Events for a specific NFT	`opensea events by-nft <chain> <contract> <token_id>`
Events for an account	`opensea events by-account <address>`

Event types:

sale

transfer

mint

listing

offer

trait_offer

collection_offer

For real-time event streaming:

opensea-stream-collection.sh <slug>

(requires

websocat

Drops + minting

Task	CLI
List drops (featured / upcoming / recent)	`opensea drops list [--type <type>]`
Drop details + stages	`opensea drops get <slug>`
Build mint tx	`opensea drops mint <slug> --minter <address> [--quantity <n>]`

Search

Task	CLI
Search collections	`opensea search <query> --types collection`
Search NFTs	`opensea search <query> --types nft`
Search tokens	`opensea search <query> --types token`
Search accounts	`opensea search <query> --types account`
Multi-type search	`opensea search <query> --types collection,nft,token`

Quick examples

Get the floor + 24h volume for Bored Apes

bash

opensea collections stats boredapeyachtclub

Find the cheapest listing for a collection

bash

opensea listings best boredapeyachtclub --limit 1

Buy an NFT (fulfill a listing)

bash

# 1. Get the best listing for a specific NFT
opensea listings best-for-nft boredapeyachtclub 1234

# 2. Get fulfillment data — order_hash from above response
./scripts/opensea-fulfill-listing.sh ethereum 0xORDER_HASH 0xYOUR_WALLET

# 3. Sign + submit the returned tx data via your wallet

Stream sales for a collection in real time

bash

./scripts/opensea-stream-collection.sh boredapeyachtclub
# Filters to sale events; pipe through jq to format

Search across types

bash

opensea search "cool cats" --types collection,nft --chains ethereum,base

Common gotchas

API key is mandatory — even the "instant" tier requires one. The bare REST API will 401 without
```
X-API-KEY
```
.
OpenSea's NFT data overlaps with Alchemy's NFT API for metadata reads. Prefer Alchemy for general NFT metadata (name, image, traits, ownership across many wallets) — OpenSea is rate-limited harder and adds marketplace flavoring you may not want. Use OpenSea when the marketplace context (listings, offers, sales history, drops) is the actual need.
Token swap aggregator exists in the OpenSea API (
```
opensea swaps quote
```
), but for pure swap flows without marketplace context,
```
lifi
```
aggregates more bridges + DEXs and is the better default. Use OpenSea swaps when the user is already in an NFT-buying flow that involves a token swap.
Privy is optional but required for end-to-end write flows. The skill returns fulfillment calldata; how it gets signed is up to the app (user wallet, Privy, or any other signer).
Order hashes from
```
listings best-for-nft
```
/
```
offers best-for-nft
```
are needed for fulfillment. Don't lose them between API calls.
Event streaming requires
```
websocat
```
; if not installed, fall back to polling
```
events by-collection
```
with the same filters.
Slug vs. address: collections are addressed by slug (e.g.,
```
boredapeyachtclub
```
), NFTs by
```
(chain, contract, tokenId)
```
. Don't mix.

Routing back to Alchemy

If during a session the user's need shifts to surfaces this skill doesn't cover:

NFT metadata reads (name, image, traits, ownership) —
```
alchemy-api
```
(NFT API) is the right path. OpenSea's NFT API is marketplace-flavored and rate-limited; Alchemy's is broader and faster.
Token prices, balances, transfer history, general token metadata —
```
alchemy-api
```
Live RPC, gas, simulation, AA, Account Kit —
```
alchemy-cli
```
(live) or
```
alchemy-api
```
(app code) or
```
agentic-gateway
```
(no API key)
Pure cross-chain token swaps —
```
lifi
```
(ecosystem skill); covers 27 bridges + 31 DEXs across 60+ chains

Maintenance: OpenSea maintains
@opensea/cli
and the underlying API; this skill itself is maintained jointly by Alchemy and OpenSea. File issues against
alchemyplatform/skills
with
[ecosystem/opensea]
in the title.

opensea

NPX Install

Tags

SKILL.md Content

OpenSea (NFT Marketplace Data + Seaport Trades)

When to use this skill

When NOT to use this skill (handoff)

Scope contract

Setup

Endpoint reference → references/marketplace.md

Marketplace queries (most-used)

Seaport trade execution

Events / monitoring

Drops + minting

Search

Quick examples

Get the floor + 24h volume for Bored Apes

Find the cheapest listing for a collection

Buy an NFT (fulfill a listing)

Stream sales for a collection in real time

Search across types

Common gotchas

Routing back to Alchemy