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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely useful behavioral context beyond that: the data is a monthly-refresh snapshot (staleness/currency), and the empty-state remediation path via the Backlinks tab.

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, front-loaded with what is returned and followed by the data-freshness caveat. Every clause carries information; nothing is redundant or padded.

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 an output schema present, the description needn't document return values, and it correctly focuses on the operational caveats an agent cannot infer: snapshot staleness and the empty-snapshot precondition. Nothing needed to call or interpret this tool is missing.

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 single limit parameter (1–25, default 20) and the fact that totals are unaffected by it are already fully documented in the schema. The description's mention of 'top referring domains' loosely maps to this parameter but adds no semantics beyond what the schema states.

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?

States a specific verb and resource (get the store's backlink profile snapshot) and enumerates the shape of the payload: total backlinks, referring domains, rank, plus top referring domains. It is clearly distinguishable from siblings like list_broken_links, list_redirect_chains, or get_search_performance, none of which cover backlink 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?

Provides clear operational context — data is only as fresh as the monthly refresh, and if no snapshot exists the merchant must open the Backlinks tab in SEO Expert once. This is actionable guidance for the empty-result case. It stops short of naming when to prefer this over an alternative sibling, but no sibling appears to overlap.

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