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

The readOnlyHint annotation already marks this as a safe, non-destructive operation. The description adds the exact API endpoint and the response envelope shape ({ valid, page_stats, data:[...] }), giving an agent a clear picture of the tool's behavior beyond the annotation.

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 short sentences that lead with the purpose, then provide the API endpoint and return shape. Every sentence earns its place with no redundant 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?

For a simple, read-only list tool with no required parameters and no output schema, the description covers the essential facts: what is listed, the API endpoint, and the response format. An agent has enough information to invoke it correctly without further research.

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 both parameters (_page and params) are already documented in the schema. The description adds nothing about parameter semantics, but it does not need to; the baseline of 3 applies because the schema carries the full burden.

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 ('List') and resource ('files in the file library (images/attachments)'), clearly distinguishing it from sibling tools like list_articles or list_categories. The API endpoint is also named, leaving no ambiguity about what the tool does.

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 clearly scopes the tool to a specific resource type ('file library (images/attachments)'), which implies when to use it relative to the list_* siblings. It does not explicitly state when not to use it or name alternatives, but the context is clear enough for tool selection.

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