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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuine behavioral context beyond that: the response is structured as headed sections plus metadata, and it surfaces linked RetailMeNot store domains and coupon categories, which is not inferable from the annotations.

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?

One tight sentence front-loads what is fetched and what comes back, then closes with the sourcing instruction for the parameter. No filler.

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 present and annotations covering read-only/open-world behavior, the description only needs to state purpose, payload shape, and parameter sourcing – all of which it does. Nothing an agent needs 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?

Schema coverage is 0% for the single slug parameter, so the description must compensate, and it does by naming the source endpoint for valid slugs. It adds no format or syntax details beyond that, but for one well-named string parameter this is adequate.

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?

States a specific verb and resource ('Get one RetailMeNot blog post by slug') and enumerates the returned payload, which cleanly separates it from the sibling retailmenot_blog_posts listing tool.

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?

'Use slugs from retailmenot_blog_posts' tells the agent exactly where the required input comes from, which is the key routing decision between this tool and its list sibling. It stops short of stating when-not to use it (e.g. for browsing or searching posts).

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