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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description's useful addition is "Costs no credits," which is billing behavior not encoded anywhere else. It does not mention failure modes (non-product URLs, blocked scraping) or return format limits, leaving the behavioral picture only partially filled in.

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?

Three short sentences: capability first, cost second, usage rationale third. Nothing is redundant and the most important information is front-loaded.

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 one-parameter read tool with no output schema, the description names the returned fields and the credit cost, and gives the reason to call it. Nothing an agent needs in order to invoke it correctly is missing.

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?

There is a single required parameter and schema coverage is 100%, with the schema already explaining it as "The product page URL." The description adds nothing about URL expectations (product-detail page vs. listing, redirects), so it sits at the high-coverage baseline.

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?

"Read a product page and return its title, description and price" gives a concrete verb, resource, and expected return fields, so the agent knows exactly what it gets back. It only hints at differentiation from generate_ad_script ("use this before generating") rather than naming it outright, so it falls just short of a 5.

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 states a clear usage context: call this before generating so the ad is grounded in page content rather than model assumptions. That is a real sequencing guideline, but it gives no when-not-to-use condition or explicit alternative for cases where scraping fails.

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