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

Annotations already declare readOnly and idempotent, but the description adds significant behavioral detail: administrators receive the complete bilingual record including drafts, while other accounts receive only a single locale with a title, summary, and URL, never the body. This is not inferable from annotations and clarifies response variance.

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 sentences, front-loaded with the primary action ('Returns one published article'), then efficiently explains the two account categories. No filler or repetition of schema details.

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, the description does not need to detail return fields. It fully covers access control, locale behavior, and draft availability for admins. For a simple read-by-ID tool, this is complete.

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 the baseline is 3. The description adds value by explaining that 'locale' is the caller's language and is ignored for administrators, and it reiterates that the response excludes the body for non-admins—context beyond the schema.

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 uses the specific verb 'Returns' with a clear resource: 'one published article.' It distinguishes this tool from siblings like get_recent_news by focusing on fetching a single article by ID, and it differentiates admin vs. non-admin behavior.

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 context for when to use the tool (fetching an article by ID) and explains role-based usage (administrators vs. other accounts). It does not explicitly name alternatives, but the sibling tool names and the scoped wording imply the appropriate use case.

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