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

Annotations declare readOnlyHint=true and the description is fully consistent with that, so no contradiction. The description adds genuine behavioral value beyond the annotations by disclosing the 25-per-side cap and enumerating the fields returned per backlink, which the schema alone does not convey.

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 short, dense sentences with no filler. The first packs result shape, scope, cap, and returned fields; the second covers project_id provenance. Key constraints are front-loaded.

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 simple read-only listing tool with an output schema and safety annotations, the description adequately covers what is returned, the cap, and required-parameter provenance. The minor gap is that it does not explicitly tie limit/status to the per-side behavior or state when this tool is preferable to backlink-related siblings.

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%, but the description compensates for the most important gap: it explains that project_id is a ranking id obtained from list_projects, which is exactly the semantic an agent needs for the required parameter. The other parameters (limit, status) are largely self-explanatory given their schema defaults and enum values.

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 states a specific verb and resource — it returns new and lost backlinks for a project — and adds concrete detail on what each result contains (Domain Score, anchor text, follow status) plus a 25-per-side cap. The new/lost framing distinguishes it from broader backlink siblings like get_backlink_profile, though it never names them 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?

The note that project_id is a ranking id from list_projects provides useful sourcing context and implies a lookup workflow. However, the description gives no explicit guidance on when to choose this tool over alternatives such as get_backlink_profile or get_audit_issues, and no exclusions are stated.

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