Check Lightning budget

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

Annotations already provide readOnlyHint and idempotentHint. Description adds that it doesn't trigger payment or side effects, and explains budget is set at startup via BUDGET_SATS (default 1000 sats). Adds useful context beyond annotations.

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?

Three sentences: first states main function, second gives usage guidance, third provides return format and budget details. No wasted words, front-loaded.

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?

No output schema but description explicitly shows return format. Covers purpose, usage, behavior, and budget configuration. Complete for a simple, param-less tool.

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?

Input schema has no parameters (100% coverage), so description doesn't need to add param info. Baseline 4 for 0 params; description is adequate.

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 it returns the remaining Lightning budget for the MCP session, specifying the verb 'returns' and resource 'remaining Bitcoin Lightning budget'. It distinguishes from siblings by mentioning usage before l402_fetch.

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?

Explicitly says 'Use this before calling l402_fetch to confirm you have enough sats — avoids wasted attempts when budget is exhausted.' Also notes it's read-only with no side effects.

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