HALOWERK marktwerk
HALOWERK provides paid endpoints that AI agents call and pay for per request via x402 on Base. No account, no API key, no signup.
OtherLiveeip155:8453Exactvia cdp
Calls · 30d
1→ 0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 16 snapshots so far.
$11.47
Verified settled volume
2,655 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0060
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-08-09 18:18Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5EThe wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
{
"docs": "https://markt.halowerk.com/llms.txt",
"name": "net_arbitrage_check",
"error": "payment_required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"asset": "USDC",
"version": "2",
"eip712Domain": {
"name": "USD Coin",
"chainId": 8453,
"version": "2",
"verifyingContract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
},
"network_name": "Base Mainnet",
"assetTransferMethod": "eip3009"
},
"payTo": "0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5E",
"amount": "6000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"pricing": "https://markt.halowerk.com/pricing",
"summary": "Checks a cross exchange price difference after taker fees and after the slippage the given size actually causes on both books, and states plainly what is left and what could not be priced.",
"resource": {
"url": "https://markt.halowerk.com/arbitrage",
"iconUrl": "https://markt.halowerk.com/favicon.svg",
"mimeType": "application/json",
"description": "Walks the visible book of every requested exchange for the given size, in both directions, and works out what remains of the raw spread: gross_spread_bps from top of book, then the taker fee of the entry tier on both sides, then the slippage the size causes on the buy book and on the sell book. net_spread_bps is the headline number, the gross value stands next to it because on its own it is misleading. Transfer costs are the part no public exchange interface publishes without a key: withdraw fee",
"serviceName": "HALOWERK marktwerk"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"size": 1,
"symbol": "BTC/USDT"
},
"type": "http",
"method": "POST",
"bodyType": "json"
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"required": [
"symbol",
"size"
],
"properties": {
"size": {
"type": "number",
"description": "Size in BASE that would be bought on one venue and sold on the other.",
"exclusiveMinimum": 0
},
"symbol": {
"type": "string",
"pattern": "^[A-Za-z0-9]{2,15}/[A-Za-z0-9]{2,15}$",
"description": "Trading pair as BASE/QUOTE, for example ETH/USDT."
},
"venues": {
"type": "array",
"items": {
"enum": [
"binance",
"coinbase",
"kraken",
"okx",
"bybit"
],
"type": "string"
},
"maxItems": 5,
"minItems": 2,
"description": "Exchanges to compare. Without it all connected ones are used.",
"uniqueItems": true
},
"include_transfer": {
"type": "boolean",
"default": true,
"description": "Whether transfer costs must be part of the verdict. They cannot be sourced publicly, so true keeps viable at null."
}
},
"additionalProperties": false
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
}
}
}
}
},
"price_usdc": "0.006",
"description": "Walks the visible book of every requested exchange for the given size, in both directions, and works out what remains of the raw spread: gross_spread_bps from top of book, then the taker fee of the entry tier on both sides, then the slippage the size causes on the buy book and on the sell book. net_spread_bps is the headline number, the gross value stands next to it because on its own it is misleading. Transfer costs are the part no public exchange interface publishes without a key: withdraw fee, network, typical transfer minutes and gas stay null with the reason named, they are never estimated. With include_transfer true, viable therefore stays null instead of claiming a profit that has not been fully costed; with include_transfer false, viable is computed on fees and slippage alone and says so. Every direction that was examined is returned with its own numbers. No execution, no recommendation, only the calculation.",
"inputSchema": {
"type": "object",
"required": [
"symbol",
"size"
],
"properties": {
"size": {
"type": "number",
"description": "Size in BASE that would be bought on one venue and sold on the other.",
"exclusiveMinimum": 0
},
"symbol": {
"type": "string",
"pattern": "^[A-Za-z0-9]{2,15}/[A-Za-z0-9]{2,15}$",
"description": "Trading pair as BASE/QUOTE, for example ETH/USDT."
},
"venues": {
"type": "array",
"items": {
"enum": [
"binance",
"coinbase",
"kraken",
"okx",
"bybit"
],
"type": "string"
},
"maxItems": 5,
"minItems": 2,
"description": "Exchanges to compare. Without it all connected ones are used.",
"uniqueItems": true
},
"include_transfer": {
"type": "boolean",
"default": true,
"description": "Whether transfer costs must be part of the verdict. They cannot be sourced publicly, so true keeps viable at null."
}
},
"additionalProperties": false
},
"price_model": "per_call",
"x402Version": 2,
"instructions": "Sign the accepted terms with an x402 client and repeat the request with the payment header.",
"outputSchema": {
"type": "object",
"properties": {
"fees": {
"type": [
"object",
"null"
]
},
"cache": {
"enum": [
"hit",
"miss"
],
"type": "string"
},
"reason": {
"type": "string"
},
"symbol": {
"type": "string"
},
"viable": {
"type": [
"boolean",
"null"
]
},
"hinweis": {
"type": "string"
},
"slippage": {
"type": [
"object",
"null"
]
},
"transfer": {
"type": "object"
},
"direction": {
"type": [
"string",
"null"
]
},
"size_base": {
"type": "number"
},
"venues_ok": {
"type": "integer"
},
"directions": {
"type": "array",
"items": {
"type": "object"
}
},
"ts_fetched": {
"type": "integer"
},
"oldest_age_ms": {
"type": [
"integer",
"null"
]
},
"venues_failed": {
"type": "array",
"items": {
"type": "object"
}
},
"net_spread_bps": {
"type": [
"number",
"null"
]
},
"quote_spread_ms": {
"type": [
"integer",
"null"
]
},
"gross_spread_bps": {
"type": [
"number",
"null"
]
},
"net_profit_quote": {
"type": [
"number",
"null"
]
},
"unavailable_fields": {
"type": "array",
"items": {
"type": "string"
}
},
"net_spread_includes_transfer": {
"type": "boolean"
}
}
},
"payment_header": "PAYMENT-SIGNATURE",
"capability_request": {
"url": "https://bedarf.halowerk.com/capabilities/request",
"cost": "free",
"method": "POST",
"description": "Missing a capability, or does the scope not fit? Report the need here - no payment required. Similar reports are bundled; the response returns an id you can check back on.",
"body_example": {
"max_price": 0.01,
"description": "what exactly is needed",
"requested_capability": "short label"
}
}
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.006USDC≈ $0.006 USD
on Base · exact scheme
Pay 0.006 USDC on Base to 0x2880…C4E5E. The signed payment is good for 5 minutes.
- Paid to
- 0x2880…C4E5E
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 6000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"asset": "USDC",
"version": "2",
"eip712Domain": {
"name": "USD Coin",
"chainId": 8453,
"version": "2",
"verifyingContract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
},
"network_name": "Base Mainnet",
"assetTransferMethod": "eip3009"
},
"payTo": "0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5E",
"amount": "6000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"body": {
"size": 1,
"symbol": "BTC/USDT"
},
"type": "http",
"method": "POST",
"bodyType": "json"
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"required": [
"symbol",
"size"
],
"properties": {
"size": {
"type": "number",
"description": "Size in BASE that would be bought on one venue and sold on the other.",
"exclusiveMinimum": 0
},
"symbol": {
"type": "string",
"pattern": "^[A-Za-z0-9]{2,15}/[A-Za-z0-9]{2,15}$",
"description": "Trading pair as BASE/QUOTE, for example ETH/USDT."
},
"venues": {
"type": "array",
"items": {
"enum": [
"binance",
"coinbase",
"kraken",
"okx",
"bybit"
],
"type": "string"
},
"maxItems": 5,
"minItems": 2,
"description": "Exchanges to compare. Without it all connected ones are used.",
"uniqueItems": true
},
"include_transfer": {
"type": "boolean",
"default": true,
"description": "Whether transfer costs must be part of the verdict. They cannot be sourced publicly, so true keeps viable at null."
}
},
"additionalProperties": false
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-08-09 18:18Z
- Last indexed by Roundhouse
- 2026-09-08 18:00Z
- Last enriched (probe, favicon, geo)
- 2026-09-20 19:15Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 16 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service HALOWERK marktwerk and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=HALOWERK%20marktwerk' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://markt.halowerk.com/arbitrage, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402, or use an organization key from https://roundhouseai.io/dashboard/team. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.