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

The readOnlyHint annotation already indicates a safe read operation, and the description adds value by enumerating the returned fields (title, body content, author, clinical reviewer, citations, metadata). This gives insight into the tool's output behavior without contradicting 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?

The description is a single, concise sentence that packs in the action, resource, method, and return value. There is no fluff or redundant information.

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 single-parameter read tool with a readOnlyHint annotation, the description covers the essential behavior: what it fetches and what it returns. No output schema exists, so enumerating return fields fills that gap adequately. The simplicity of the tool means this is sufficient contextual completeness.

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 schema already describes the single parameter 'slug' with 'Article slug.' at 100% coverage. The description reinforces that the slug identifies the article to fetch, which is helpful, but it does not add significant extra meaning beyond what the schema provides.

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 a specific action ('Fetch a single article') and resource ('from ADHD in Teens by slug'). It differentiates this tool from siblings like list_articles and search_articles by indicating it retrieves one specific article via an identifier.

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 phrase 'by slug' implies usage when the slug is already known, and that this tool targets a single article rather than listing or searching. However, it does not explicitly name alternatives or state when not to use this tool, leaving the guidance implicit rather than direct.

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