fetch_page

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

The description discloses many behavioral traits: converts HTML to Markdown, anchor handling, relative vs absolute resolution, rejection of off-site URLs and path traversal, truncation at ~200KB, and different return formats. It also states 'Read-only', matching the annotations. This adds significant context beyond the readOnly/destructive hints, such as error behavior and metadata in json mode.

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 structured with clear sections (Args, Returns, Examples) and starts with a one-sentence summary. It is longer than minimal but every part adds value: parameter clarifications, return format, examples, and constraints. No filler or redundancy. Slightly verbose but justified by the tool's complexity.

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?

The description fully covers the tool's behavior: inputs, outputs, error handling, truncation, edge cases, and examples. It even mentions integration with search results and list_sites. Even though the input schema includes an output schema reference, the description explains the return shapes in detail, making the tool self-contained. Sibling context is well integrated.

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 coverage is 100%, so baseline is 3. The description adds meaning beyond the schema: it explains that site is used only for relative paths and ignored for absolute URLs, that anchors focus on a section, and that url_or_path can be an absolute URL on a configured site or a site-relative path. It also clarifies the response_format options and their payloads, exceeding what the schema states.

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 opens with a specific verb and resource: 'Fetch a page from a Verso documentation site and return it as Markdown.' It clearly distinguishes from siblings by explaining it fetches page content, while list_sites lists sites, list_kinds lists kinds, and search finds content. The scope (single page/section with anchor) is also stated.

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 explicitly instructs when to use the tool: to read a chapter, a single entry via #anchor, or resolve a search hit. It references list_sites for the site alias and search for passing the url field, showing context. It does not explicitly say 'when not to use' but the URL constraints and examples imply alternatives. This is clear guidance, though not as explicit as naming an alternative tool.

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