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

The description goes well beyond annotations by disclosing that the tool 'Never returns pass', the possible verdicts ('present, fail, or unverifiable'), and that values like 'a was-price, a different variant's price, a shipping cost, or a tax figure' can satisfy presence. It also states the check_type and payment method. No contradiction with readOnlyHint/openWorldHint is present.

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 efficient and information-dense. Every sentence contributes: purpose, non-return of 'pass', examples, verdict types, usage guidance, alternative tool, scope, and cost. It is front-loaded with the core distinction ('Presence only...') and remains focused despite its length.

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?

The description covers all essential context: what the tool does, when to use it, when not to, behavioral nuances, limitations (server-rendered pages), and pricing. Since an output schema exists, the absence of return-format detail is acceptable. It is fully adequate for an AI agent to select and invoke the tool correctly.

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?

While the schema already provides 100% coverage for parameter descriptions, the tool description adds crucial interpretation for the 'claim' parameter: presence is not correctness, and gives concrete examples of what counts as present. This adds semantic value beyond the schema definitions.

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 tool performs a presence-only check: 'confirms the value appears on the page, NOT that it is the right answer to what was asked.' It explicitly differentiates from the sibling tool verify_web_field by naming it and stating when to call it instead. The title also reinforces the purpose.

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 explicit usage guidance: 'Use it as a cheap screen before a full check, or when you already know what the value means and only need to confirm it still appears on the page.' It also provides a clear exclusion: 'If your decision depends on the value being the right value, call verify_web_field instead.' It even notes scope (server-rendered pages) and cost.

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