# Bittensor Subnet Burn-Cost History API

> Bittensor Subnet Burn-Cost History API is a paid API for AI agents from api.carbon-cashmere.de, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Returns a time series of Bittensor subnet-creation burn costs (TAO) over the last N hours, with rolling min/max/avg and percent-change statistics.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/bittensor/burn-history
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-carbon-cashmere-de-7f8bb4b9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_k3lKWMfISVGhVXNUhUoQW

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability api-carbon-cashmere-de-7f8bb4b9
```

Example prompt: Show me the Bittensor subnet-creation burn cost trend over the last 168 hours — I want to see the time series plus rolling min, max, average, and percent change so I can gauge whether demand for new subnets is heating up or cooling down.

## When to prefer this

Use this endpoint when you need historical burn-cost trend data for Bittensor subnet creation, specifically time-series data with statistical aggregates (min/max/avg/change_pct). Prefer this over general Bittensor metagraph endpoints when the focus is on economic demand signals for subnet registration rather than neuron-level or validator data.

## Known failure modes

- Invalid 'hours' parameter (outside 1-720 range) returns a 400 error
- Upstream Subtensor node unavailability may cause 503 or stale data
- Payment failure (x402) if USDC balance is insufficient
- Response may be truncated for very large windows (e.g. 720 hours) due to payload size

## How this service works

Professional crypto market intelligence. Real-time prices, signals, and market scoring.

## Output

A time series array of TAO burn-cost data points over the requested window (up to 720 hours), plus summary statistics: rolling minimum, maximum, average, and percentage change — enabling trend analysis of subnet registration demand on the Bittensor network.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {
   "hours": "168"
  }
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "hours": 168,
  "stats": {
   "avg_tao": 751.3,
   "max_tao": 820,
   "min_tao": 680,
   "change_pct": 8.2
  },
  "series": [
   {
    "ts": "2026-04-11T00:00:00Z",
    "burn_cost_tao": 680.5
   }
  ],
  "current_burn_cost_tao": 793.11
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-carbon-cashmere-de-7f8bb4b9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.carbon-cashmere.de](https://www.zero.xyz/host/api.carbon-cashmere.de/llms.txt)