# Bittensor Block Metrics API

> Bittensor Block Metrics 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 2026-09-14).

Returns recent per-block aggregated Bittensor network events including neuron registrations, weight sets, bond sets, child key sets, stake changes, root claims, balance transfers, and total TAO.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/subtensor-derivatives/block-metrics
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-carbon-cashmere-de-8a0f61a8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gl0mKQq8incEbiPipRgLY

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-8a0f61a8
```

Example prompt: Show me the latest per-block Bittensor network activity — I want to see neuron registrations, stake additions and removals, weight sets, and total TAO moved across the most recent blocks.

## When to prefer this

Use this endpoint when you need aggregated on-chain Bittensor event data at the block level, especially for monitoring network activity trends, staking flows, neuron registration rates, or weight-setting behavior over recent blocks. Prefer over raw node queries for pre-aggregated, ready-to-use metrics.

## Known failure modes

- Subtensor lite node unavailable — returns 5xx error
- No recent blocks available — returns empty dataset
- Rate limit exceeded — returns 429
- Invalid query parameters — returns 400 with error message

## How this service works

Recent per-block aggregation of Bittensor events: neuron_registrations, weight_sets, bond_sets, child_key_sets, stake_added/removed, root_claimed, balance_transfers + total TAO.

## Output

A collection of recent per-block Bittensor event aggregations including counts/values for neuron_registrations, weight_sets, bond_sets, child_key_sets, stake_added, stake_removed, root_claimed, balance_transfers, and total TAO per block.

## Example request

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

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "limit": 60,
  "blocks": [
   {
    "weight_sets": 1,
    "block_number": 8204514,
    "total_events": 120,
    "balance_transfers": 4,
    "neuron_registrations": 0,
    "balance_transfer_total_tao": 142.5
   }
  ],
  "returned": 60
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-carbon-cashmere-de-8a0f61a8/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)