markfetch

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

No annotations are present, so the description carries full responsibility for behavioral disclosure. It does reveal that the output is readable content converted to Markdown and includes metadata, and it hints that render uses a headless browser for JS-heavy pages. However, it omits potential failure modes, rate limits, network dependencies, or what happens with non-HTML content, which are relevant for a web-fetching tool.

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 two sentences with no redundancy. The core action and output are front-loaded in the first sentence, and the second sentence provides a concise, actionable tip. Every word earns its place, and the description is easy to scan for an agent.

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 no output schema, the description helpfully enumerates what the Markdown output will include (title, byline, excerpt, metadata). It also covers the main invocation point (URL) and the key optional behavior (render). It is complete enough for a straightforward fetching tool, though it could mention default behavior for mode and links, and clarify 'Pro' constraints.

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 schema already documents all parameters. The description adds minimal value by suggesting when to set render=true for JavaScript-heavy pages, which slightly extends the schema's 'Render JavaScript in a headless browser first (Pro plan)'. This is a marginal addition, so the baseline score of 3 is appropriate.

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 the action ('Fetch a web page') and the specific output ('readable content as Markdown, with title, byline, excerpt and metadata'). It distinguishes the tool from a generic fetcher by specifying the transformation to Markdown and the extra metadata. The verb and resource are explicit, making the tool's purpose immediately understandable.

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 clear context for when to use the tool: whenever a web page's readable Markdown content is needed. It also provides a conditional usage hint for the render parameter ('Set render=true for JavaScript-heavy pages'). With no sibling tools, explicit comparison is not necessary, but the description could be slightly stronger by mentioning when to use mode=full vs article.

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