semrush_rank_difference

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, so the safe, read-only nature is clear. The description's 'Get' aligns with this but adds no further behavioral details (e.g., data freshness, rate limits, or what 'winners and losers' implies). Since annotations carry most of the burden, a 3 is appropriate.

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 sentence, which is concise but sacrifices necessary information about parameters. It is front-loaded with the purpose, but the brevity leaves gaps. It could include parameter hints without becoming verbose.

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?

Given the simple schema (2 params, no output schema), the description should still explain the inputs and what 'winners and losers' means in terms of ranking changes. It omits parameter descriptions and doesn't clarify what domain/context is needed (e.g., does it require a domain parameter? Not in schema). The tool is incomplete for confident use.

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?

The input schema has 2 parameters ('database' with default 'us', 'limit') with 0% description coverage. The description does not mention either parameter, failing to add meaning beyond the schema. It should explain that 'database' is a country code and 'limit' controls the number of results.

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 clearly states the tool's purpose: 'Get winners and losers — domains with biggest ranking changes'. It uses a specific verb ('Get') and resource ('winners and losers'/'domains with biggest ranking changes'), which distinguishes it from sibling tools that focus on different aspects like domain overview or rank history.

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?

No guidance is provided on when to use this tool versus alternatives like semrush_domain_rank or semrush_domain_rank_history. There is no mention of prerequisites, context, or scenarios where this tool is preferred.

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