pay-invoice

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

No annotations are provided, and the description fails to disclose important behavioral traits such as irreversible fund transfer, balance requirements, or the full impact of sendAll (emptying wallet). The agent is left unaware of consequences.

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 concise (one sentence), but it sacrifices accuracy for brevity by falsely mentioning a 'description' field.

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?

For a payment tool with significant side effects, the description lacks essential context about success/failure, balance requirements, and error handling. The sendAll behavior is only hinted in the schema, not the description.

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?

Schema coverage is 100% (baseline 3), but the description adds no value and misleads by stating a 'description' parameter that doesn't exist, reducing clarity.

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 action (pay a bolt11 invoice), but incorrectly mentions a 'description' parameter that does not exist in the schema, which could confuse an agent. It also does not differentiate from sibling tools like pay-lightning-address or pay-offer.

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?

No guidance is provided on when to use this tool vs alternatives (e.g., pay-lightning-address, pay-offer). No prerequisites or exclusions are mentioned.

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