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loop-mcp

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com.loopxxi/loop-mcpv2.4.0 Domain verified

15 pay-per-call Bitcoin and developer tools, paid in sats over Lightning (L402).

Crypto & Web3 Utilities

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https://mcp.loopxxi.com/mcp

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Tool list from our last check. Connect live to refresh it.

base64_convert Read-only

Encode UTF-8 text to Base64 or decode Base64 safely, with standard and URL-safe alphabets.

datastring, required

Text or Base64 data, up to 100 KB.

actionstring, required

url_safeboolean

Use the URL-safe alphabet without padding.

loop-mcp MCP server | mcptry

Tools (15)

base64_convert

Encode UTF-8 text to Base64 or decode Base64 safely, with standard and URL-safe alphabets.

read-only

Argument	Type	Description
data*	string	Text or Base64 data, up to 100 KB.
action*	string
url_safe	boolean	Use the URL-safe alphabet without padding.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "data",
    "action"
  ],
  "properties": {
    "data": {
      "type": "string",
      "description": "Text or Base64 data, up to 100 KB."
    },
    "action": {
      "enum": [
        "encode",
        "decode"
      ],
      "type": "string"
    },
    "url_safe": {
      "type": "boolean",
      "description": "Use the URL-safe alphabet without padding."
    }
  }
}

btc_price

Get the current Bitcoin price in USD and other major currencies. Source: mempool.space. Real-time.

read-only

No arguments.

Input schema (JSON)

{
  "type": "object",
  "required": [],
  "properties": {}
}

btc_send_decision

Returns a composited send-or-wait recommendation for a Bitcoin transaction. Fetches live mempool and fee data, then outputs a machine-actionable verdict (SEND_NOW, WAIT, or URGENT_ONLY) with fee rates in sat/vB, mempool pressure level, and estimated savings if you wait. Ideal for agents that need a single decision call instead of parsing multiple raw mempool endpoints.

read-only

Argument	Type	Description
urgency	string	How time-sensitive is your transaction? low=economy, medium=default, high=next-block.

Input schema (JSON)

{
  "type": "object",
  "required": [],
  "properties": {
    "urgency": {
      "enum": [
        "low",
        "medium",
        "high"
      ],
      "type": "string",
      "description": "How time-sensitive is your transaction? low=economy, medium=default, high=next-block."
    }
  }
}

csv_to_json

Convert CSV, TSV, semicolon, or pipe-delimited text into structured JSON with bounded row output.

read-only

Argument	Type	Description
csv*	string	Delimited text, up to 100 KB.
header	boolean	Use the first row as object keys. Default true.
max_rows	integer	Maximum data rows to return. Default 100.
delimiter	string	Delimiter name. Default comma.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "csv"
  ],
  "properties": {
    "csv": {
      "type": "string",
      "description": "Delimited text, up to 100 KB."
    },
    "header": {
      "type": "boolean",
      "description": "Use the first row as object keys. Default true."
    },
    "max_rows": {
      "type": "integer",
      "maximum": 1000,
      "minimum": 1,
      "description": "Maximum data rows to return. Default 100."
    },
    "delimiter": {
      "enum": [
        "comma",
        "tab",
        "semicolon",
        "pipe"
      ],
      "type": "string",
      "description": "Delimiter name. Default comma."
    }
  }
}

hash_generate

Generate a SHA-256 or SHA-512 digest in hexadecimal or Base64 form.

read-only

Argument	Type	Description
text*	string	Input text, up to 100 KB.
encoding	string	Output encoding. Default hex.
algorithm	string	Hash algorithm. Default sha256.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "text"
  ],
  "properties": {
    "text": {
      "type": "string",
      "description": "Input text, up to 100 KB."
    },
    "encoding": {
      "enum": [
        "hex",
        "base64"
      ],
      "type": "string",
      "description": "Output encoding. Default hex."
    },
    "algorithm": {
      "enum": [
        "sha256",
        "sha512"
      ],
      "type": "string",
      "description": "Hash algorithm. Default sha256."
    }
  }
}

json_extract

Extract one value from JSON using a simple dot path with array indexes, for example users[0].email.

read-only

Argument	Type	Description
json*	string	JSON text, up to 100 KB.
path*	string	Dot path such as user.profile.name or users[0].email.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "json",
    "path"
  ],
  "properties": {
    "json": {
      "type": "string",
      "description": "JSON text, up to 100 KB."
    },
    "path": {
      "type": "string",
      "description": "Dot path such as user.profile.name or users[0].email."
    }
  }
}

json_validate

Validate JSON, identify its root type, and return normalized JSON plus a SHA-256 content hash.

read-only

Argument	Type	Description
json*	string	JSON text to validate, up to 100 KB.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "json"
  ],
  "properties": {
    "json": {
      "type": "string",
      "description": "JSON text to validate, up to 100 KB."
    }
  }
}

jwt_decode

Decode JWT header and payload claims locally without verifying the signature. The response always marks verification as false.

read-only

Argument	Type	Description
token*	string	JWT compact serialization, up to 20 KB.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "token"
  ],
  "properties": {
    "token": {
      "type": "string",
      "description": "JWT compact serialization, up to 20 KB."
    }
  }
}

lightning_address_resolve

Resolve a Lightning Address ([email protected]) to a payable BOLT11 invoice for a given amount. Handles the full LNURL-pay protocol internally. Returns the invoice plus min/max sendable amounts for validation.

read-only

Argument	Type	Description
address*	string	Lightning Address in [email protected] format.
amount_sats*	integer	Amount you want to send, in satoshis.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "address",
    "amount_sats"
  ],
  "properties": {
    "address": {
      "type": "string",
      "description": "Lightning Address in [email protected] format."
    },
    "amount_sats": {
      "type": "integer",
      "minimum": 1,
      "description": "Amount you want to send, in satoshis."
    }
  }
}

optimal_send_window

Bitcoin transaction timing intelligence. Returns a congestion forecast for the next 1-4h, a recommended UTC send window when fees are projected at/below your target, a fee trajectory (rising/stable/falling) with a calibrated confidence score, next-block minimum fee, confirmation targets for 3/6/144 blocks, and an RBF-viability flag. A synthesis layer above raw fee data — the decision an autonomous payment agent needs before broadcasting. Source: mempool.space.

read-only

Argument	Type	Description
hours_ahead	integer	How far ahead to search for the optimal window (1-6h, default 4).
target_sat_vb	number	Your fee ceiling in sat/vB. The recommended window targets at-or-below this rate. Omit to get the lowest-projected window.

Input schema (JSON)

{
  "type": "object",
  "required": [],
  "properties": {
    "hours_ahead": {
      "type": "integer",
      "maximum": 6,
      "minimum": 1,
      "description": "How far ahead to search for the optimal window (1-6h, default 4)."
    },
    "target_sat_vb": {
      "type": "number",
      "description": "Your fee ceiling in sat/vB. The recommended window targets at-or-below this rate. Omit to get the lowest-projected window."
    }
  }
}

text_analyze

Return deterministic text statistics, estimated tokens, reading time, and a SHA-256 content hash.

read-only

Argument	Type	Description
text*	string	Text to analyze, up to 100 KB.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "text"
  ],
  "properties": {
    "text": {
      "type": "string",
      "description": "Text to analyze, up to 100 KB."
    }
  }
}

timestamp_convert

Convert Unix seconds, Unix milliseconds, RFC3339, or ISO dates into normalized UTC timestamp forms.

read-only

Argument	Type	Description
from	string	Input format. Default auto.
value*	string	Timestamp value.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "value"
  ],
  "properties": {
    "from": {
      "enum": [
        "auto",
        "unix",
        "unix_ms",
        "rfc3339",
        "date"
      ],
      "type": "string",
      "description": "Input format. Default auto."
    },
    "value": {
      "type": "string",
      "description": "Timestamp value."
    }
  }
}

tx_decode_explain

Fetch a Bitcoin transaction by txid and return a structured, agent-ready summary: type (P2WPKH/P2TR/P2SH/etc.), input/output counts, fees, fee rate in sat/vB, confirmation status, RBF flag, SegWit/Taproot flags, and a one-line agent_summary string ready for LLM context injection. Saves 500-2000 tokens vs parsing raw TX JSON.

read-only

Argument	Type	Description
txid*	string	Bitcoin transaction ID (64 hex characters).

Input schema (JSON)

{
  "type": "object",
  "required": [
    "txid"
  ],
  "properties": {
    "txid": {
      "type": "string",
      "maxLength": 64,
      "minLength": 64,
      "description": "Bitcoin transaction ID (64 hex characters)."
    }
  }
}

url_parse

Parse an HTTP or HTTPS URL into normalized scheme, host, port, path, query, and fragment fields without fetching it.

read-only

Argument	Type	Description
url*	string	Absolute HTTP or HTTPS URL, up to 4,096 characters.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "url"
  ],
  "properties": {
    "url": {
      "type": "string",
      "description": "Absolute HTTP or HTTPS URL, up to 4,096 characters."
    }
  }
}

uuid_generate

Generate one to one hundred cryptographically random RFC 4122 UUID version 4 identifiers.

read-only

Argument	Type	Description
count	integer	Number of UUIDs. Default 1.

Input schema (JSON)

{
  "type": "object",
  "required": [],
  "properties": {
    "count": {
      "type": "integer",
      "maximum": 100,
      "minimum": 1,
      "description": "Number of UUIDs. Default 1."
    }
  }
}