# BaseDue Token Liquidity & Exit Price Checker

> BaseDue Token Liquidity & Exit Price Checker is a paid API for AI agents from api.firstmention.uk, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-29).

Returns liquidity depth, best DEX pool, spot price, and exit capacity for an ERC-20 token on Base, estimating how much USD can be extracted before hitting a price impact limit.

## Facts

- Endpoint: GET https://api.firstmention.uk/s/basedue/price?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/basedue-token-liquidity-exit-price-checker-e798a698
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ckHD01KNnTnxKsSYjx9Et

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 basedue-token-liquidity-exit-price-checker-e798a698
```

Example prompt: Check how much liquidity is available to exit a $5000 position in the token at 0xcbb7c0000ab88b473b1f5afd9ef808440eed33bf on Base, with a max price impact of 1%.

## When to prefer this

Use this endpoint when you need on-chain liquidity analysis specifically for tokens on the Base network, particularly to estimate exit capacity before executing a large sell. Prefer this over generic price APIs when you need DEX-level depth, pool identification, price impact modeling, and slippage estimation rather than just a spot price. Best suited for DeFi agents performing pre-trade due diligence or portfolio liquidation planning on Base.

## Known failure modes

- Invalid or non-existent token address returns error or ok:false
- Token with no liquidity pools on Base returns empty venues array
- Requested exit size exceeds available liquidity, returning ok:false with impact details
- Malformed 0x address format causes input validation failure
- Rate limiting or payment failure (x402) blocks the request

## How this service works

Pay-per-call HTTP APIs, paid with x402 in USDC on Base (eip155:8453): agentkit, api-change-check, basedue, basewatch, chainread, check-sanctions, chgwatch, company-facts, composite, edgar, feednews, pageaudit, solcheck, token-dd, txpreflight, walletcheck, webmd, webread, websearch, x402index. Each operation describes its service.

## Output

Returns a JSON object with: ok status, ETH/USD price, per-token results including best pool address and venue, maximum USD that can be extracted within the price impact limit, spot price in USD, quote asset depth, token reserves, price impact percent, slippage USD amount, and a verdict on whether the requested exit size is feasible. Also includes a note clarifying that Uniswap V3 pools are excluded and results are lower bounds.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "token"
     ],
     "properties": {
      "size": {
       "type": "number",
       "description": "/exit only: USD position size"
      },
      "token": {
       "type": "string",
       "description": "ERC-20 token address on Base (0x + 40 hex)"
      },
      "impact": {
       "type": "number",
       "description": "/exit only: max acceptable price impact percent (default 1)"
      },
      "tokens": {
       "type": "string",
       "description": "up to 3 comma-separated token addresses"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "chain": {
       "type": "string"
      },
      "summary": {
       "type": "object",
       "properties": {
        "poolCount": {
         "type": "number"
        },
        "bestDepthUsd": {
         "type": "number"
        },
        "bestDepthGrade": {
         "type": "string"
        }
       }
      },
      "verdict": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "note": "Capacity is a LOWER BOUND: Uniswap V3 pools are excluded from the size model. Constant-product model; comparable in order of magnitude, not exact.",
  "chain": "base",
  "ethUsd": 2343.51,
  "results": [
   {
    "ok": true,
    "best": {
     "pool": "0x2578365b3dfa7ffe60108e181efb79feddec2319",
     "venue": "aerodrome",
     "maxUsdOut": 3230.39,
     "quoteAsset": "WETH",
     "maxTokenSell": 0.040595
    },
    "size": {
     "ok": false,
     "pool": "0x2578365b3dfa7ffe60108e181efb79feddec2319",
     "venue": "aerodrome",
     "usdOut": 4923.79,
     "impactPct": 1.5242,
     "slippagePct": 1.524,
     "slippageUsd": 76.21,
     "requestedUsd": 5000
    },
    "token": "0xcbb7c0000ab88b473b1f5afd9ef808440eed33bf",
    "symbol": "cbBTC",
    "venues": [
     {
      "pool": "0x2578365b3dfa7ffe60108e181efb79feddec2319",
      "venue": "aerodrome",
      "maxUsdOut": 3230.39,
      "quoteAsset": "WETH",
      "maxTokenSell": 0.040595,
      "spotPriceUsd": 80380.2,
      "quoteDepthUsd": 324023.6,
      "tokenReserveUi": 4.029
     }
    ],
    "impactLimitPct": 1
   }
  ],
  "endpoint": "exit"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/basedue-token-liquidity-exit-price-checker-e798a698/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.firstmention.uk](https://www.zero.xyz/host/api.firstmention.uk/llms.txt)