# Glassnode Mempool Total Transaction Size

> Glassnode Mempool Total Transaction Size is a paid API for AI agents from x402.glassnode.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Returns the total size of all Bitcoin transactions currently waiting in the mempool, measured in virtual bytes (vByte), as a time series.

## Facts

- Endpoint: GET https://x402.glassnode.com/v1/metrics/mempool/txs_size_sum
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/glassnode-mempool-total-transaction-size-a8d757c3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3PK3qxMhdDu2fv-HqRRmL

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 glassnode-mempool-total-transaction-size-a8d757c3
```

Example prompt: Pull the total mempool transaction size for Bitcoin from Glassnode — I want the 24-hour interval data in JSON so I can see how congested the mempool has been.

## When to prefer this

Use this endpoint when you need historical or current Bitcoin mempool congestion data measured in virtual bytes, specifically sourced from Glassnode's on-chain analytics platform. Prefer this over generic blockchain explorers when you need structured time series data for quantitative analysis or trend monitoring of mempool load.

## Known failure modes

- Missing required 'a' query parameter (asset) returns 400 error
- Invalid asset symbol other than BTC returns validation error
- Payment not included or insufficient USDC (x402 payment required) returns 402 Payment Required
- Invalid interval or format enum value returns 400 error
- Upstream Glassnode data unavailable returns 503 or timeout

## How this service works

Mempool Total Size of Transactions — The total size of all transactions waiting in the mempool, denoted in virtual bytes (vByte). Data by Glassnode.

## Output

An array of time-stamped data points, each containing a Unix timestamp ('t') and the total mempool size value in virtual bytes ('v'), representing daily snapshots of all pending Bitcoin transactions in the mempool.

## 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": [
      "a"
     ],
     "properties": {
      "a": {
       "enum": [
        "BTC"
       ],
       "type": "string",
       "description": "Asset symbol, e.g. BTC, ETH"
      },
      "c": {
       "enum": [
        "native"
       ],
       "type": "string",
       "description": "Currency for denominated values, e.g. usd, native"
      },
      "f": {
       "enum": [
        "csv",
        "json"
       ],
       "type": "string",
       "description": "Response format: json or csv"
      },
      "i": {
       "enum": [
        "24h"
       ],
       "type": "string",
       "description": "Time interval / resolution, e.g. 24h, 1w, 1month"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "array",
     "items": {
      "type": "object",
      "properties": {
       "t": {
        "type": "number"
       },
       "v": {
        "type": "number"
       }
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/glassnode-mempool-total-transaction-size-a8d757c3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.glassnode.com](https://www.zero.xyz/host/x402.glassnode.com/llms.txt)