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

With no annotations supplied, the description carries the full burden and does disclose the important behavior: it is paid ($0.005 USDC), payable on Base or Solana, requires no account or API key, and failed calls are not charged. Gaps remain around timeouts, redirect handling, and non-HTML or missing-metadata responses.

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?

Five short sentences, front-loaded with the 'Paid.' warning and the operation, then cost, then payment details, then endpoint. Nothing is redundant and the reader can stop at any sentence once satisfied.

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?

For a one-parameter, no-output-schema tool the description covers what it returns, what it costs, which chains settle payment, and that failures are free. Combined with the fully documented schema and endpoint URL, an agent has everything needed to call it correctly.

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% and the single 'url' parameter is already documented as 'Page URL, http(s)'. The description adds no further meaning about supported schemes, length limits, or how redirects are followed, so the baseline 3 applies.

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?

States a specific verb and a precisely enumerated resource: 'Get a web page's title, meta description and Open Graph tags'. The enumeration itself distinguishes it from buy_fetch_fetch-html (full HTML) and buy_fetch_fetch-headers (headers), though neither sibling is named explicitly.

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?

Usage context is implied rather than stated: an agent can infer this is the cheap, metadata-only alternative when raw HTML or headers are not needed. There is no explicit 'use this instead of X when Y' routing, and no guidance on what to do when a page has no meta tags.

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