lightning-mcp

Create Lightning Invoice

create_invoice

Generate a Lightning invoice to request a payment in satoshis, optionally including a memo.

Instructions

Create a Lightning invoice to receive a payment.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "amountSats": "<amountSats>"
    },
    "name": "create_invoice"
  }
}

Input Schema

Name	Required	Description	Default
`amountSats`	Yes	Amount in satoshis
`description`	No	Invoice description / memo

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.0Sep 13, 2026

TDQS

B3.1/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full behavioral burden. It does not disclose whether the created invoice expires, whether creation is idempotent, what wallet/account state is required, or what the tool returns. For a mutation tool with zero annotation coverage this is a real gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single short, front-loaded sentence with no wasted words. It is efficient but so terse that it borders on under-specification rather than tight conciseness.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a creation tool with no annotations and no output schema, the description omits the most important operational details: what the call yields (the invoice/BOLT11 string), expiry behavior, and any prerequisites. An agent can guess the purpose but not the result or constraints.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so both parameters (amountSats, description/memo) are already fully documented in the schema. The description mentions none of them and adds no format or constraint detail, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('Create') and resource ('Lightning invoice') plus intent ('to receive a payment'), distinguishing it from siblings like pay_invoice and decode_invoice which operate on existing invoices. However, it does not explicitly name any sibling for differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The clause 'to receive a payment' implies the scenario (you want to be paid), which is adequate implied usage. There is no explicit when-to-use vs. alternatives guidance or exclusion, and nothing routes the agent away from pay_* siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server