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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false. The description adds context about the data source (Wikimedia Analytics REST API) and that no authentication is required, which is useful beyond annotations. It does not describe response specifics (e.g., pagination, limit) but given the output schema exists and annotations fully cover safety, this is sufficient.

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 concise and front-loaded with the core purpose, followed by return details, filtering options, and data source info. Every sentence contributes useful information without redundancy. It reads naturally and is well-structured.

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 the output schema exists (which covers return structure) and annotations fully handle safety and idempotence, the description covers all essential usage aspects: how to request daily vs monthly data, filtering by access, and the data source. An agent can correctly invoke this tool without additional hints.

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?

The input schema has 100% description coverage, with each parameter explained (e.g., day pattern includes 'all-days', project examples provided). The description adds minimal extra meaning, only reinforcing the dual-mode behavior and access filter, 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 states a specific verb ('List') and resource ('most-viewed articles on a Wikimedia project'), with explicit scope (single day vs full month). It also outlines the return fields (title, view count, rank). This clearly distinguishes it from sibling tools like wikimedia-analytics.pageviews.per_article, which focuses on a single article's views.

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 provides clear usage context: it specifies that this tool is for listing top articles, and implicitly contrasts with other pageviews tools (e.g., per_article for individual article views). It also notes the access method filter and the special value 'all-days' for monthly aggregation, leaving little ambiguity about when to use it.

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