Roundhouse

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.

TradingLiveeip155:8453Exactvia cdp
https://markt.halowerk.com/token
Calls · 30d
1→ 0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 18 snapshots so far.
$11.47
Verified settled volume
2,654 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0020
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 2026-08-12 04:28Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5E

The 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": "token_price_confidence",
  "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": "2000",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 300
    }
  ],
  "pricing": "https://markt.halowerk.com/pricing",
  "summary": "Token price in US dollars for a contract address on any covered chain, with the confidence measure of the source passed through unchanged, the age of the value in seconds, the 24 hour change and an explicit warning whenever confidence is low, missing or the value is stale.",
  "resource": {
    "url": "https://markt.halowerk.com/token",
    "iconUrl": "https://markt.halowerk.com/favicon.svg",
    "mimeType": "application/json",
    "description": "Takes a chain key and a contract address, or one of a short list of globally unambiguous symbols. A symbol that is not on that list is refused with 400 and a pointer to the address rather than resolved to a guess: the same ticker exists on every chain, and the imitations carry it deliberately. price_usd, decimals and symbol come from the source as they are. confidence is passed through unsmoothed, and this is the point of the endpoint: where the source omits the field, the answer carries null an",
    "serviceName": "HALOWERK marktwerk"
  },
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "body": {
            "chain": "base",
            "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
          },
          "type": "http",
          "method": "POST",
          "bodyType": "json"
        }
      },
      "schema": {
        "type": "object",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "required": [
          "input"
        ],
        "properties": {
          "input": {
            "type": "object",
            "required": [
              "type",
              "method",
              "bodyType",
              "body"
            ],
            "properties": {
              "body": {
                "type": "object",
                "properties": {
                  "chain": {
                    "type": "string",
                    "default": "base",
                    "pattern": "^[a-z0-9_-]{2,24}$",
                    "description": "Chain key of the source, for example ethereum, base, arbitrum, optimism, polygon, bsc. Required together with address."
                  },
                  "symbol": {
                    "type": "string",
                    "pattern": "^[A-Za-z0-9]{2,10}$",
                    "description": "Alternative to address, only for globally unambiguous symbols: BTC, ETH, SOL, BNB, XRP, ADA, AVAX, DOT, MATIC, LINK, UNI, AAVE, DOGE, LTC, ATOM. Anything else is refused with 400."
                  },
                  "address": {
                    "type": "string",
                    "pattern": "^(0x[a-fA-F0-9]{40}|[A-Za-z0-9]{32,44})$",
                    "description": "Contract address of the token. EVM address as 0x with 40 hex digits, or the mint address on non EVM chains."
                  }
                },
                "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": "0.002",
  "description": "Takes a chain key and a contract address, or one of a short list of globally unambiguous symbols. A symbol that is not on that list is refused with 400 and a pointer to the address rather than resolved to a guess: the same ticker exists on every chain, and the imitations carry it deliberately. price_usd, decimals and symbol come from the source as they are. confidence is passed through unsmoothed, and this is the point of the endpoint: where the source omits the field, the answer carries null and a warning, never a default that would read as high confidence. data_age_seconds is computed against the timestamp of the quote, not against the moment of the request, so a cached upstream value cannot look fresh. warnings is an array with one entry per triggered rule, and the thresholds behind them travel in thresholds_used. change_24h_percent is fetched separately and stays null with a named reason when the source has no history for the token, instead of being derived from a single observation. A token the source does not cover produces 404 with the chain keys that are known, because a wrong chain key and an unknown token look identical in the raw response.",
  "inputSchema": {
    "type": "object",
    "properties": {
      "chain": {
        "type": "string",
        "default": "base",
        "pattern": "^[a-z0-9_-]{2,24}$",
        "description": "Chain key of the source, for example ethereum, base, arbitrum, optimism, polygon, bsc. Required together with address."
      },
      "symbol": {
        "type": "string",
        "pattern": "^[A-Za-z0-9]{2,10}$",
        "description": "Alternative to address, only for globally unambiguous symbols: BTC, ETH, SOL, BNB, XRP, ADA, AVAX, DOT, MATIC, LINK, UNI, AAVE, DOGE, LTC, ATOM. Anything else is refused with 400."
      },
      "address": {
        "type": "string",
        "pattern": "^(0x[a-fA-F0-9]{40}|[A-Za-z0-9]{32,44})$",
        "description": "Contract address of the token. EVM address as 0x with 40 hex digits, or the mint address on non EVM chains."
      }
    },
    "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": {
      "note": {
        "type": "string"
      },
      "query": {
        "type": "object"
      },
      "stale": {
        "type": "boolean"
      },
      "source": {
        "type": "array"
      },
      "symbol": {
        "type": [
          "string",
          "null"
        ]
      },
      "decimals": {
        "type": [
          "integer",
          "null"
        ]
      },
      "warnings": {
        "type": "array",
        "items": {
          "type": "object"
        }
      },
      "price_usd": {
        "type": [
          "number",
          "null"
        ]
      },
      "confidence": {
        "type": [
          "number",
          "null"
        ]
      },
      "fetched_at_iso": {
        "type": "string"
      },
      "stale_as_of_iso": {
        "type": [
          "string",
          "null"
        ]
      },
      "thresholds_used": {
        "type": "object"
      },
      "data_age_seconds": {
        "type": [
          "integer",
          "null"
        ]
      },
      "change_24h_percent": {
        "type": [
          "number",
          "null"
        ]
      }
    }
  },
  "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.

0.002USDC≈ $0.002 USD
on Base · exact scheme

Pay 0.002 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
2000 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": "2000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "chain": "base",
          "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
        },
        "type": "http",
        "method": "POST",
        "bodyType": "json"
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method",
            "bodyType",
            "body"
          ],
          "properties": {
            "body": {
              "type": "object",
              "properties": {
                "chain": {
                  "type": "string",
                  "default": "base",
                  "pattern": "^[a-z0-9_-]{2,24}$",
                  "description": "Chain key of the source, for example ethereum, base, arbitrum, optimism, polygon, bsc. Required together with address."
                },
                "symbol": {
                  "type": "string",
                  "pattern": "^[A-Za-z0-9]{2,10}$",
                  "description": "Alternative to address, only for globally unambiguous symbols: BTC, ETH, SOL, BNB, XRP, ADA, AVAX, DOT, MATIC, LINK, UNI, AAVE, DOGE, LTC, ATOM. Anything else is refused with 400."
                },
                "address": {
                  "type": "string",
                  "pattern": "^(0x[a-fA-F0-9]{40}|[A-Za-z0-9]{32,44})$",
                  "description": "Contract address of the token. EVM address as 0x with 40 hex digits, or the mint address on non EVM chains."
                }
              },
              "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
2026-08-12 04:28Z
Last indexed by Roundhouse
2026-09-11 04:30Z
Last enriched (probe, favicon, geo)
2026-09-21 07:45Z
x402 version
2
Max timeout
300s
Liveness probe
HTTP 402
Report

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. 18 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.

Open skill.md
Show 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/token, 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.