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

No annotations are provided, so the description carries full responsibility for behavioral disclosure. It mentions 'unique' and 'specific URL', which hints at filtering/dedup behavior, but it does not disclose what 'unique' means, how backlinks are collected, response format, pagination, rate limits, or any side effects. For a read-only tool, this is a minimal disclosure.

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 that gets straight to the point. It is front-loaded with the action ('Get') and resource ('unique backlinks'), with no unnecessary words or filler.

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 is simple, with only 2 parameters and no output schema, but it has many similar sibling tools. The description does not clarify what 'unique' means or how this differs from get_page_backlinks, which could lead to incorrect tool selection. Given the lack of annotations and the close siblings, a bit more context (e.g., 'returns deduplicated backlinks, unlike get_page_backlinks') would be needed for full completeness.

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%, with both 'url' and 'num' described in the input schema. The description adds the qualifier 'unique' and 'specific URL', which reinforces the 'url' parameter's purpose but does not add significant new meaning beyond the schema. Baseline for high coverage is 3.

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 'Get unique backlinks for a specific URL' clearly states a verb ('Get'), a resource ('backlinks'), and a scope ('for a specific URL'). The inclusion of 'unique' distinguishes it from sibling tools like get_page_backlinks, which likely returns all backlinks, and from domain-level tools like get_domain_backlinks.

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 implies usage for a specific URL and hints at uniqueness ('unique backlinks'), but it does not explicitly state when to use this tool over alternatives like get_page_backlinks or get_unique_domain_backlinks. No exclusions or alternative suggestions are provided, leaving the selection criteria implicit.

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