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

The description adds substantial context beyond the annotations: it discloses that this is a paid tool ($0.25 USDC on Base or Arbitrum One), explains the x402 v2 PAYMENT-SIGNATURE header requirement and paid_url invocation, and clarifies that no orders are placed. These are exactly the operational and safety details an agent needs for a non-read-only paid tool.

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 compact and most sentences carry necessary operational information: paid status, price, payment mechanism, documentation link, and the no-orders boundary. The opening is slightly cryptic, but there is little wasted text overall.

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?

With an output schema and full parameter descriptions available, the description does not need to explain return values or parameter formats. However, for a complex paid tool, it still leaves the core concept of 'delayed scan' and 'expressions' underdefined, so an agent understands the payment flow better than it understands the actual delivered result.

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 100%, so the schema already documents all five parameters, including query examples and the supported budget values. The description only reinforces that omitting budget_usd means uncapped, which is already stated in the schema, so it does not add meaningful semantics beyond the structured field.

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 gestures at the tool's function with 'Shop an idea: delayed scan' and lists ticker/comparison/theme inputs, but the core output remains vague because terms like 'delayed scan', 'shelf', and 'expressions' are not defined. It does distinguish idea generation from order placement, but an agent cannot confidently state what the tool returns without opening the output schema.

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 gives a scenario ('Shop an idea') and a boundary ('Ideas only — no orders placed'), plus a budget default, but it does not say when to choose this tool over siblings such as research_paper, diligence_pack, or trust_report. There is no explicit when-to-use, when-not-to-use, or alternative-routing guidance.

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