karte.halowerk.com
HALOWERK provides paid endpoints that AI agents call and pay for per request via x402 on Base. No account, no API key, no signup.
MediaLiveeip155:8453Exactvia cdp
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.
$0.0050
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 2026-08-11 14:48Z
—
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://karte.halowerk.com/llms.txt",
"name": "elevation_profile",
"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": "5000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"pricing": "https://karte.halowerk.com/pricing",
"resource": {
"url": "https://karte.halowerk.com/v1/elevation-profile",
"mimeType": "application/json",
"description": "Takes a list of coordinates and returns the elevation at each, the distance and gradient between consecutive points, total ascent and descent, the steepest ramp with the segment it belongs to, and the mean gradient over the whole line. An optional resample interval inserts intermediate points along the great circle between the given ones, which is what makes a steepest-ramp figure meaningful on a route described by a handful of corners."
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"points": [
{
"lat": 50.73,
"lon": 7.12,
"label": "Rhein bei Bonn"
},
{
"lat": 50.6675,
"lon": 7.2078,
"label": "Drachenfels"
}
],
"resample_m": 200
},
"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": [
"points"
],
"properties": {
"points": {
"type": "array",
"items": {
"type": "object",
"required": [
"lat",
"lon"
],
"properties": {
"lat": {
"type": "number",
"maximum": 90,
"minimum": -90,
"description": "Latitude, WGS 84."
},
"lon": {
"type": "number",
"maximum": 180,
"minimum": -180,
"description": "Longitude, WGS 84."
},
"label": {
"type": "string",
"maxLength": 80,
"description": "Optional name, echoed back."
}
},
"additionalProperties": false
},
"maxItems": 300,
"minItems": 2,
"description": "The line, in order. At least two coordinates."
},
"resample_m": {
"type": "number",
"maximum": 10000,
"minimum": 10,
"description": "Insert intermediate points every this many metres along each segment. Without it only the given points are sampled. Billing follows the resulting sample count, capped at 300."
},
"interpolate": {
"type": "boolean",
"default": true,
"description": "Bilinear interpolation between the four surrounding grid values. Off returns the nearest grid value unchanged."
},
"include_points": {
"type": "boolean",
"default": true,
"description": "Return the per-point list. Off returns only the summary figures."
}
},
"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": "0.005000",
"description": "Takes a list of coordinates and returns the elevation at each, the distance and gradient between consecutive points, total ascent and descent, the steepest ramp with the segment it belongs to, and the mean gradient over the whole line. An optional resample interval inserts intermediate points along the great circle between the given ones, which is what makes a steepest-ramp figure meaningful on a route described by a handful of corners. The data is Copernicus DEM GLO-30, free for commercial use and read straight from the AWS Open Data bucket over HTTP range requests, so only the blocks actually needed are fetched rather than a local copy of the dataset. Four limits are stated in every answer rather than buried. It is a surface model, not a terrain model: over forest the measurement is the tree canopy and over built-up ground the roof, a difference that runs to twenty or forty metres in central Europe, so a profile for a path under trees is not what this returns. The grid is 30 metres, so anything between grid points is bilinearly interpolated and not measured, and a narrow cutting or embankment can disappear entirely between two samples. Water surfaces and voids carry fill values in the dataset, and those come back as null with the reason and the raw value, never as an elevation of zero — and where a coordinate falls on open sea there is no tile at all, which is reported as such. Ascent and descent are summed only over segments where both ends have a real measurement, and the number of segments skipped for that reason is returned, because a total over an incomplete profile is worth less than the knowledge that it is incomplete. Attribution is required when the result is used: Copernicus DEM, produced using EU data.",
"inputSchema": {
"type": "object",
"required": [
"points"
],
"properties": {
"points": {
"type": "array",
"items": {
"type": "object",
"required": [
"lat",
"lon"
],
"properties": {
"lat": {
"type": "number",
"maximum": 90,
"minimum": -90,
"description": "Latitude, WGS 84."
},
"lon": {
"type": "number",
"maximum": 180,
"minimum": -180,
"description": "Longitude, WGS 84."
},
"label": {
"type": "string",
"maxLength": 80,
"description": "Optional name, echoed back."
}
},
"additionalProperties": false
},
"maxItems": 300,
"minItems": 2,
"description": "The line, in order. At least two coordinates."
},
"resample_m": {
"type": "number",
"maximum": 10000,
"minimum": 10,
"description": "Insert intermediate points every this many metres along each segment. Without it only the given points are sampled. Billing follows the resulting sample count, capped at 300."
},
"interpolate": {
"type": "boolean",
"default": true,
"description": "Bilinear interpolation between the four surrounding grid values. Off returns the nearest grid value unchanged."
},
"include_points": {
"type": "boolean",
"default": true,
"description": "Return the per-point list. Off returns only the summary figures."
}
},
"additionalProperties": false
},
"price_basis": {
"unit": "10 Abtastpunkte",
"basis": "Abgerechnet werden die uebergebenen Punkte.",
"units": 1,
"resampled": false,
"input_points": 0,
"sample_points": 0
},
"price_model": {
"kind": "per_unit",
"unit": "10 Abtastpunkte",
"max_usdc": "0.03",
"min_usdc": "0.005",
"max_units": 30,
"unit_price_usdc": "0.001"
},
"x402Version": 2,
"instructions": "Sign the accepted terms with an x402 client and repeat the request with the payment header.",
"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.
0.005USDC≈ $0.005 USD
on Base · exact scheme
Pay 0.005 USDC on Base to 0x2880…C4E5E. The signed payment is good for 5 minutes.
- Paid to
- 0x2880…C4E5E
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 5000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"asset": "USDC",
"version": "2",
"eip712Domain": {
"name": "USD Coin",
"chainId": 8453,
"version": "2",
"verifyingContract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
},
"network_name": "Base Mainnet",
"assetTransferMethod": "eip3009"
},
"payTo": "0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5E",
"amount": "5000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"body": {
"points": [
{
"lat": 50.73,
"lon": 7.12,
"label": "Rhein bei Bonn"
},
{
"lat": 50.6675,
"lon": 7.2078,
"label": "Drachenfels"
}
],
"resample_m": 200
},
"type": "http",
"method": "POST",
"bodyType": "json"
}
},
"schema": {
"type": "object",
"$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": [
"points"
],
"properties": {
"points": {
"type": "array",
"items": {
"type": "object",
"required": [
"lat",
"lon"
],
"properties": {
"lat": {
"type": "number",
"maximum": 90,
"minimum": -90,
"description": "Latitude, WGS 84."
},
"lon": {
"type": "number",
"maximum": 180,
"minimum": -180,
"description": "Longitude, WGS 84."
},
"label": {
"type": "string",
"maxLength": 80,
"description": "Optional name, echoed back."
}
},
"additionalProperties": false
},
"maxItems": 300,
"minItems": 2,
"description": "The line, in order. At least two coordinates."
},
"resample_m": {
"type": "number",
"maximum": 10000,
"minimum": 10,
"description": "Insert intermediate points every this many metres along each segment. Without it only the given points are sampled. Billing follows the resulting sample count, capped at 300."
},
"interpolate": {
"type": "boolean",
"default": true,
"description": "Bilinear interpolation between the four surrounding grid values. Off returns the nearest grid value unchanged."
},
"include_points": {
"type": "boolean",
"default": true,
"description": "Return the per-point list. Off returns only the summary figures."
}
},
"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
- 2026-08-11 14:48Z
- Last indexed by Roundhouse
- 2026-09-10 14:30Z
- Last enriched (probe, favicon, geo)
- 2026-09-21 05:15Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 400
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.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service karte.halowerk.com 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=karte.halowerk.com' 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://karte.halowerk.com/v1/elevation-profile, 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.