getLinkPreview

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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint. Description adds synchronous nature, immediate results, that it does not count against monthly audit quota, and requires OAuth authentication. No contradictions.

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?

Four sentences, no wasted words, front-loaded with core purpose, then usage triggers, then behavioral notes, then alternative. Perfectly structured.

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 a single parameter, good annotations, and an output schema, the description covers purpose, usage, behavioral constraints, and the return format in a summary. Completeness is high.

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% with a single 'url' parameter that already has a description. The description does not add additional parameter semantics beyond what the schema provides.

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 verb 'Check' and resource 'URL', specifies the platforms (Facebook, Twitter/X, LinkedIn, Google), and distinguishes itself from sibling tool 'startSiteAudit' for full multi-page audits.

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 lists example user queries that trigger the tool ('check the link preview', 'how does this page look when shared', 'check my og tags', etc.) and provides an explicit alternative ('For a full multi-page audit... use startSiteAudit instead').

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