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

With no annotations, the description fully carries the burden of disclosure. It details the payment mechanism ($0.01 per call via x402, USDT on X Layer), the first-call trial, and the retry requirement (PAYMENT-SIGNATURE header). It also notes no account/signup needed. No contradictions.

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 relatively long (5 sentences) but each sentence serves a purpose: purpose, payment model, trial, comparison to sibling, and no-account requirement. It is front-loaded with the core action. Slight wordiness does not detract significantly.

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 no output schema, the description explains that the tool returns macro series names ranked highest first, which is adequate. It covers payment, trial, and comparison to pitch. The one-parameter input is simple. Slightly more detail on return fields would improve completeness, but it is sufficient.

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% with a single parameter (limit, number, default 5, max 45). The description does not add additional context for this parameter beyond what the schema provides, so a baseline of 3 is appropriate.

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 verb (scan), resource (all 45 macro series), and the specific action (return those reading HIGHEST, ranked most-high first). It distinctly separates this tool from its sibling scan_bottoms and from pitch by noting that pitch only provides a count.

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 description provides explicit guidance on when to use this tool versus the sibling pitch: 'The free pitch tool tells you HOW MANY are at a top right now; this names them.' It also highlights that no symbol selection is needed. It lacks explicit when-not-to-use scenarios but is sufficiently clear for an agent.

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