# BTC Mempool Fee Distribution

> BTC Mempool Fee Distribution is a paid API for AI agents from api.carbon-cashmere.de, paid per call via x402, $0.03/call, status down (last checked 2026-09-14).

Returns the Bitcoin mempool fee distribution — transaction counts per fee-rate bucket (sat/vB) — revealing fee pressure and congestion across priority tiers.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/mempool/distribution
- Price: $0.03/call
- Payment: x402
- Status: down
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-carbon-cashmere-de-1ec6c98b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Hki2P26tdASh9uRFe6ZUx

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-1ec6c98b
```

Example prompt: Show me the current Bitcoin mempool fee distribution broken down by sat/vB bucket so I can figure out the right fee rate for my transaction right now.

## When to prefer this

Use this endpoint when you need a granular, bucket-level view of the Bitcoin mempool fee landscape — ideal for fee estimation logic, optimal transaction timing, or detecting mempool congestion spikes. Prefer over simple median-fee endpoints when you need the full distribution shape.

## Known failure modes

- Mempool data temporarily unavailable — upstream Bitcoin node sync issue (503)
- Rate limit exceeded for the endpoint (429)
- Payment not processed — x402 payment required (402)
- Malformed request parameters result in 400 error
- Empty distribution array returned during very low mempool activity

## How this service works

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

## Output

An array of fee-rate buckets (e.g., 0-1, 1-2, 2-5, ..., 200+ sat/vB) each annotated with the number of unconfirmed transactions waiting at that fee rate, giving a full picture of mempool depth and fee pressure across priority levels.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "distribution": [
   {
    "bucket_0_1": 500,
    "bucket_1_2": 300,
    "bucket_2_5": 200,
    "total_tx_count": 45000
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-carbon-cashmere-de-1ec6c98b/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)