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

The description adds real context beyond the annotations: output ordering ('strongest first'), the metric ranges (authority 0-100), the exact comparison semantics, and the side effect 'Saved in the user's Puley history' — which explains why readOnlyHint is false despite this being a lookup tool. It stops short of noting that the tool is open-world/networked and may be slow or rate-limited, which the openWorldHint implies.

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 sentences, both loaded with information: the base behavior first, then the compare branch, then the persistence note. No filler or restatement of the tool name.

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?

With only two parameters, no output schema, and no field descriptions, the description does a good job describing both the inputs and the shape of the return. A minor gap is the absence of any indication of how many referring sites are returned or how the list is bounded.

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 0%, so the description must carry the parameter meaning, and it largely does: domain is the site being analyzed, and compare_with is explicitly 'a competitor's website' that changes the result set. It does not state whether domain should include a protocol or www prefix, leaving format ambiguity.

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 resource (a domain's backlink profile) and enumerates the returned metrics — linking sites, total links, authority 0-100 — plus the comparison mode. It does not explicitly distinguish itself from neighbors like check_links, check_site, or competitor_report, so an agent must infer the boundary rather than read it.

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 is implied: call it for backlink research, and add compare_with for a competitor gap analysis ('sites that link to the competitor but not to this site'). There is no explicit statement of when to prefer check_links or check_site, nor any prerequisite or cost guidance, so the routing decision is left to inference.

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