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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds value beyond that by disclosing the return payload shape ('metadata and body paragraphs') and the fact that it targets public articles, but says nothing about failure modes for paywalled or invalid URLs.

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?

A single tight sentence with no filler, front-loaded on the resource. It is efficient, though the terseness is also the source of its missing guidance.

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?

An output schema exists, so return-value detail is not required, and the annotations carry the safety profile. However, with one undocumented required parameter and no routing guidance among four sibling marketwatch tools, the definition leaves real gaps for an agent deciding whether and how to call it.

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?

There is one required parameter with 0% schema description coverage, so the schema contributes no semantic detail. The description implicitly signals that a single article is identified, but never states that 'url' must be a MarketWatch article URL or where such a URL comes from, which is the key semantic the agent needs.

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-resource pairing ('one public MarketWatch article') and enumerates the payload ('metadata and body paragraphs'), which is far more than a restatement of the name. It does not explicitly distinguish itself from marketwatch_headlines or marketwatch_news, but the singular 'one ... article' framing makes the scope discernible.

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 gives no indication of when to use this tool versus marketwatch_headlines, marketwatch_news, or marketwatch_sections, and no prerequisite such as needing a URL sourced from one of those listing tools. Usage must be inferred entirely from the name.

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