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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false. The description repeats 'Read-only' and adds that output comes as HTML and a React component, which is useful formatting context. It does not add behavioral details beyond the annotations, such as permission requirements or error behavior, so a baseline 3 is appropriate.

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?

Two sentences with zero waste: the first sentence front-loads what the tool returns, and the second provides precise usage context. Every sentence earns its place and the structure is easy to scan.

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 simple read-only code-generation tool with 100% schema coverage, full annotations, and an output schema, the description covers purpose and usage adequately. Return values are handled by the output schema, so the description does not need to explain them.

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 all three parameters, including the mode and pageType enums, are fully documented in the schema. The description adds no additional parameter meaning or usage constraints. Baseline 3 is correct when the schema does the heavy lifting.

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 states a specific verb and resource: 'Get ready-to-paste code that puts a checkout page, form, or event on a website.' It explicitly distinguishes the tool from sibling creation tools by naming create_checkout_page, create_form, and create_event as preceding actions. An agent can tell this is a code-generation/embed tool, not a creator or updater.

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 gives clear triggering conditions: 'Use it right after create_checkout_page, create_form, or create_event when the user is building or editing a website, or when the user asks to add a checkout, buy button, ticket form, or signup form to their site.' This covers when to use it well. However, it does not name alternatives or explicitly state when not to use it, so it falls short of the top score.

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