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

Annotations already declare readOnlyHint=true, so the safe/read-only nature is covered. The description adds useful behavioral detail about the return format: plain text plus URL and Markdown URL. It does not discuss missing-slug behavior, but for a simple read-only fetch this is a minor gap.

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?

One short, front-loaded sentence communicates the resource, the scoping parameter, and the output format. Every word earns its place, with no filler or repetition.

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 tool with one required parameter and no output schema, the description adequately covers what input is needed and what will be returned. It is slightly incomplete because it omits any error/not-found behavior and does not explain how the returned URL or Markdown URL should be interpreted, but it is still sufficient for basic invocation.

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 0%, so the description must compensate, but it only says 'by slug.' This adds little beyond the parameter name and regex pattern already present in the schema. It does not explain what a valid slug looks like, how to obtain one, or why it uniquely identifies an article.

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 specifies the verb and resource: retrieving the full text of one article by slug. It also states the output format, setting it apart from sibling tools like search_articles, which would be for finding rather than fetching a specific article.

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 makes it clear this is the tool to use when you already have a specific slug and need the full article text. It does not explicitly discuss when not to use it or mention alternatives such as search_articles, but the context is unambiguous enough for a simple fetch tool.

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