Fetch a web page as Markdown

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

Even with readOnlyHint and openWorldHint annotations, the description adds substantial behavioral context: robots.txt compliance, rate limiting, caching behavior, diff responses on refetch, and automatic PDF handling. This goes well beyond what annotations convey and fully discloses side effects and state handling.

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 compact and front-loaded with the main purpose. It packs a lot of information into four sentences without fluff, though the use of semicolons and slashes makes it slightly dense. Every sentence contributes value, but it could be broken into a list for better scannability.

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 explains primary return types (Markdown, outline, screenshot) and cache states (unchanged/diff). It covers key behaviors like PDF handling and mode selection. Missing details about error responses or rate limit headers, but for a fetch tool this is fairly complete given the 7 parameters and sibling context.

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?

All parameters have schema descriptions, so the baseline is high. The description adds extra meaning to mode (auto/markdown/outline/screenshot) and explains caching behavior that affects force_full and max_tokens, enriching beyond the schema. It does not detail page, section, or selector semantics, but the schema already covers those.

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 tool's function: 'Fetch a web page as Markdown' with specific details like 'low-impact, token-efficient' and supported modes. It distinguishes from the screenshot sibling by explicitly listing screenshot as a mode, and links is not mentioned but the core purpose is unambiguous.

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 implies use cases through features like caching and diff responses for repeated fetches, and 'token-efficient' suggests when token economy matters. However, it does not explicitly state when to use this tool instead of the sibling 'screenshot' or 'links' tools, nor does it provide exclusions or alternatives.

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