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

No annotations exist, so the description carries the full behavioral burden. It does disclose the ordering algorithm (live web search frequency for the week, network pick first, curated community order as fallback) and that ranked_by reveals which order was used — genuinely useful non-obvious behavior. It stops short of stating that the data is read-only, cache/freshness implications, or how many wallets are returned.

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?

Front-loaded with the purpose, then a compact enumeration of returned fields and the ordering rule. Mostly tight, but the trailing fragment 'Free.' and the broken line-wrapping format add little and slightly interrupt the read.

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 zero-parameter list tool with an output schema, the description goes beyond the minimum by explaining what each item contains and how ordering is determined (including the ranked_by indicator). Nothing an agent needs to select or call this tool is missing.

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?

Zero parameters, so there is no parameter semantics to explain; the baseline of 4 applies. The description correctly requires no input from the caller and does not invent spurious parameters.

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?

States a concrete resource with scope: Lightning wallets a newcomer can install to pay a Tollbooth invoice, and enumerates what each entry contains (store links, one-line description, custody flag, in-app bitcoin purchase). This is clearly distinguishable from siblings like list_services or resolve_service, which deal with network services rather than wallet recommendations.

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?

Usage context is explicit: for someone who needs a wallet to pay a Tollbooth invoice. However, it never names an alternative or a when-not condition (e.g., what to use if the user already has a wallet, or how this relates to list_services/resolve_service). Clear context, but no routing guidance.

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