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

The description adds substantial behavioral context beyond the annotations: per-row billing, a 20-row cap, no charges for 4xx/5xx responses, and semicolon-delimited text output. These details are not present in any structured field and are critical for cost-aware invocation.

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?

Three short sentences, each earning its place: purpose, cost/limits, and response format. It is front-loaded with the core purpose and contains no filler or repetition.

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 low-complexity tool with two primitive required parameters and an output schema, the description covers everything an agent needs: what it returns, cost constraints, row limits, and response formatting. Nothing essential 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 coverage is 100%, with both `domain` and `database` having descriptions and examples. The description does not add parameter-level meaning beyond the schema, so the baseline of 3 applies.

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 identifies the resource ('domains competing with a target') and the context ('Google organic search'), which distinguishes it from SEMrush backlinks, domain overview, and Similarweb tools. However, it lacks an explicit verb like 'Returns' or 'Lists,' so it falls just short of a 5.

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 intended use case is implied: use this when you need domains competing with a target in Google organic search. But the description never explicitly states when to prefer this over sibling tools such as get_similarweb_keyword_competitors or get_semrush_domain_overview, and gives no exclusion criteria.

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