# Bitcoin Mining Pool Concentration & 51% Risk Check

> Bitcoin Mining Pool Concentration & 51% Risk Check is a paid API for AI agents from bitcoin-network.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Returns the share of recent Bitcoin blocks by mining pool, including top-3 concentration, Herfindahl-Hirschman Index (HHI), and a 51% attack risk verdict.

## Facts

- Endpoint: GET https://bitcoin-network.x402tookit.com/btc-mining-pools?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bitcoin-mining-pool-concentration-51-risk-check-b1db0fae
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gB1mBKOu2OFA8efj_XJXB

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 bitcoin-mining-pool-concentration-51-risk-check-b1db0fae
```

Example prompt: What's the current Bitcoin mining pool concentration? Show me which pools dominate, the HHI score, and whether there's any 51% attack risk — use the last 7 days as the window.

## When to prefer this

Use this endpoint when you need a structured, pre-computed mining pool concentration analysis with a built-in 51% risk verdict and HHI score, rather than raw blockchain data you'd have to aggregate yourself. Ideal for monitoring Bitcoin network health, security dashboards, or any agent that needs a quick go/no-go safety signal on mining centralization.

## Known failure modes

- Invalid window parameter returns error or default behavior
- Data source unavailable causes degraded flag to be true with partial results
- Network timeout from upstream blockchain data provider
- Empty pool list if no block data is available for the requested window

## How this service works

Mining pool share of recent Bitcoin blocks with concentration (top-3 share, HHI) and the 51 percent check.

## Output

Returns a JSON object containing: list of mining pools with block count and share percentage, top-1 and top-3 share percentages, HHI concentration index, a 51%-attack verdict string, human-readable summary, array of reasons supporting the verdict, total blocks in window, time window label, data source and URL, a degraded flag if data quality is reduced, and a disclaimer.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "window": {
       "type": "string",
       "description": "24h, 3d, 1w (default), 1m or 3m"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "hhi": {
       "type": [
        "null",
        "number"
       ]
      },
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "pools": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "object",
        "properties": {
         "pool": {
          "type": [
           "null",
           "string"
          ]
         },
         "blocks": {
          "type": [
           "null",
           "number"
          ]
         },
         "sharePct": {
          "type": [
           "null",
           "number"
          ]
         },
         "emptyBlocks": {
          "type": [
           "null",
           "number"
          ]
         }
        }
       }
      },
      "blocks": {
       "type": [
        "null",
        "number"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "window": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "sourceUrl": {
       "type": [
        "null",
        "string"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
      
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bitcoin-mining-pool-concentration-51-risk-check-b1db0fae/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bitcoin-network.x402tookit.com](https://www.zero.xyz/host/bitcoin-network.x402tookit.com/llms.txt)