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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It does not mention that the tool makes a network request, handles redirects, may fail on non-HTML URLs, or what happens when no Open Graph tags exist. This is a significant gap for a network-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 a single concise sentence with no wasted words. It immediately conveys the tool's core function without any filler or repetition.

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 tool has a single parameter and no output schema, so the description needs to explain what the expected return values are. It only says 'Open Graph metadata' without detailing which fields (e.g., title, image, description) will be returned or how they are structured. This leaves the agent guessing about the output shape.

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?

The input schema already covers the only parameter ('url') with a description, so the baseline is 3. The tool description adds no new parameter-specific details; it only repeats the 'URL' concept. It does clarify that the URL is used for extracting Open Graph metadata, but this does not go beyond what the schema implies.

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 specifies the action ('Extract') and the exact resource ('Open Graph metadata from a URL'). It distinguishes itself from sibling tools like extract_pdf_text and html_to_text by focusing specifically on Open Graph metadata.

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?

No explicit when-to-use or alternative guidance is provided, but the specific mention of Open Graph metadata implies its intended use case (e.g., fetching social media preview data). This is enough for an agent to infer the basic scenario, but it lacks exclusions or comparisons with related tools.

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