Check hreflang

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

With no annotations provided, the description carries the behavioral burden. It states the tool crawls and validates rather than modifies data, and adds an important domain behavior: declarations Google cannot verify from both ends are dropped entirely. It stops short of describing output or crawl side effects, but for a read-only validation tool this is solid coverage.

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?

Two focused sentences with no filler. The first front-loads the action and resource, the second provides a concise, valuable explanation of why this validation matters. Every sentence earns its place.

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 read-only tool with fully documented parameters and no output schema, the description covers what the tool does, what it validates, and why it is important. The only notable omission is a description of the return format, but no output schema exists and the validation focus makes the expected result inferable.

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%, so the two parameters (site and maxPages) are already fully documented in the input schema. The description does not add parameter-level detail, which is acceptable but not value-adding, 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?

The description names a specific verb, resource, and scope: 'Crawl the site and validate its hreflang across pages.' It enumerates the exact checks performed (reciprocity, self-reference, language/region codes, duplicate x-default), which makes it unmistakable and clearly distinct from general crawl or validation siblings like crawl_site and validate_structured_data.

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 gives useful context for when this tool is needed: hreflang faults are invisible page-by-page and affect the whole cluster, so this is the tool for cross-page cluster validation. It does not explicitly name alternatives or say when not to use it, but the reasoning is clear enough for an agent to route to it appropriately.

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