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

Annotations already declare readOnly, openWorld, idempotent, non-destructive. The description adds the data source (standardebooks.org Atom feed), explicit return fields, and the 'most-recent first' ordering. This goes beyond annotations without contradicting them.

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 concise sentences: the first explains the operation and output, the second gives data source and auth. Every word earns its place, no fluff.

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?

Given a single optional parameter and an output schema that presumably details the returned object, the description covers operation, ordering, limit, return fields, data source, and authentication. Nothing important 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 describes the limit parameter with min, max, default, and the fixed feed size. The description mentions 'up to the latest 15' which aligns with the schema but adds little new meaning. Schema coverage is 100%, so baseline 3 is appropriate.

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 verb and resource: 'Get the most recently released Standard Ebooks (up to the latest 15), most-recent first.' It also lists the specific return fieldsais. It does not explicitly name the sibling tool 'standard-ebooks.books.search' to differentiate, but 'recently released' vs search is sufficiently distinct.

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 implies usage: when you want recent releases, with the ordering and limit. It does not state when NOT to use or mention the alternative search tool. It adds context like 'no auth required' and data source, but no explicit exclusions or routing to siblings.

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