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

Discloses non-execution of JS, no access control bypass, and caching behavior. Annotations already indicate read-only, idempotent, and non-destructive; description adds useful contextual limits without contradiction.

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?

Three concise sentences, front-loaded with the tool's output and key constraints. No wasted words.

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?

Given the output schema exists, the description need not detail return values. It sufficiently covers usage constraints and parameter guidance for a tool with many siblings.

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 provides full descriptions for both parameters (url pattern, fresh default). Description only reiterates cache behavior for fresh, adding minimal value beyond what the schema already 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?

Description clearly lists extracted fields (title, description, author, dates, canonical) and states the tool is for public HTTP(S) resources, distinguishing it from siblings that extract other types of content.

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?

Explicitly states to use only for public HTTP(S) resources and notes it does not execute JavaScript or bypass access controls. Provides guidance on the fresh parameter (cache reuse vs. new fetch). Lacks explicit comparison to siblings but is sufficient.

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