liveauth_mcp_lnurl

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states that the tool retrieves an invoice, but does not clarify side effects, return format, expiration, or whether it is a read-only operation. The mention of 'lnget-compatible' is vague and adds little transparency.

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

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

The description is short and front-loaded, but the two sentences are somewhat redundant: 'Get the Lightning invoice' is repeated as 'retrieve the BOLT11 invoice.' It could be condensed into a single sentence without losing information, so it is not maximally concise.

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

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

The tool has only one parameter with good schema coverage, but no output schema and no annotations. The description does not explain what the response looks like, potential errors, or any behavioral context like payment flow or invoice validity. Given the lack of structured metadata, this is insufficient for an agent to fully understand the tool's role.

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

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

The input schema already provides 100% coverage by describing quoteId as 'The quoteId from the start response.' The description adds no additional meaning about the parameter, so the baseline score of 3 is appropriate.

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

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

The description clearly states the tool's function: 'Get the Lightning invoice for a session' and also mentions 'retrieve the BOLT11 invoice for payment.' This provides a specific verb and resource, but it does not explicitly differentiate from sibling tools like start, status, or charge, so it does not reach a 5.

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

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

The description says 'Use this to retrieve the BOLT11 invoice for payment,' which implies the tool is for obtaining an invoice after starting a session. However, it does not explicitly state when to use it versus alternatives, nor does it mention any prerequisites or exclusions. This falls under implied usage rather than clear guidance.

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