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

The annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is partially covered. The description adds meaningful behavioral context beyond the annotations: the tool queries a 'live' price, performs an 'optional public wallet-balance sufficiency' check, and 'without signing or moving funds' clarifies exactly what side effects are absent.

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 a single, well-structured sentence that front-loads the main purpose and then lists return categories and safety boundaries. Every clause earns its place, and there is no redundant repetition of the tool name or schema fields.

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 tool with 7 parameters and no output schema, the description gives a useful high-level summary of return categories but not enough detail about how parameters affect behavior or what the actual response shape looks like. It is adequate for understanding the tool's role, but an agent would likely need to inspect schemas or examples to confidently invoke it with the right combination of fields.

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 description coverage is only 14%, so the description must compensate for undocumented parameters, but it does not. It references 'optional public wallet-balance sufficiency' which maps to wallet_address, but it never explains product, max_price_usd, supports_x402, supported_assets, supported_networks, or autonomous_spend_allowed. The schema itself is mostly silent, leaving an agent without enough parameter-level guidance.

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 names an explicit purpose ('buyer-side compatibility preflight') and a specific resource (SALT19/x402 payment), and states what it returns: live price, Base/USDC requirement, optional wallet-balance sufficiency, and next action. It also signals a key boundary by saying it does not sign or move funds, which distinguishes it from authorization or execution tools like x402-authorization-handoff.

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 phrase 'buyer-side compatibility preflight' clearly implies this tool should be used before any signing or fund movement, and 'without signing or moving funds' reinforces the safe preflight context. However, it does not explicitly name sibling tools or state when not to use it, leaving some routing to inference rather than explicit guidance.

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