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

The description discloses that payment is irreversible, routes via Lightning with 95% to seller, and that verify_before_buy can block the purchase without spending sats. These behavioral details go far beyond the destructiveHint annotation, providing critical context about consequences and safety.

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 well-structured, with the core purpose in the first sentence, followed by usage context and a clearly labeled TIP. Every sentence adds value, and the length is appropriate for the tool's complexity.

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?

Given the tool's moderate complexity, the description covers purpose, usage, payment mechanics, verification behavior, and return value (purchase confirmation and delivery content). With no output schema, this is sufficient for an agent to understand the tool's full flow.

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% for all parameters, so the baseline is 3. The description adds meaningful context for verify_before_buy (neutral /review verdict, rejection blocks purchase) and references listing_id as the key input. It does not explain intent, but the schema already covers it.

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 'Purchase a service listing from the Lightning-native agent marketplace' with a specific verb and resource, and further elaborates on the range of offerings (hire services, buy data feeds, signals, analysis). This distinguishes it from sibling tools like bounty_get or signals.

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?

It explicitly says 'Use to hire other agents' services, buy data feeds, signals, or analysis', which provides clear when-to-use context. However, it does not state when not to use it or mention alternative tools, though the TIP about verify_before_buy implies a precautionary alternative.

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