Count search results

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

With readOnlyHint=true already indicating a safe read operation, the description adds valuable behavioral context: 'without spending query credits' and 'quick' disclose cost and performance traits. It does not detail response format, but the count semantics are implied, so it goes beyond the annotation without contradicting it.

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 two sentences, front-loaded with the core action, and every part earns its place. It is concise and free of redundant wording, achieving high efficiency.

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 one-parameter tool with no output schema, the description fully covers what the tool does, when to use it, and its cost behavior. The return value (count) is clear from the description, making it contextually complete.

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% for the single 'query' parameter, matching the description's 'Shodan search query.' The description adds no new syntax or format details beyond the schema, so the baseline 3 is appropriate.

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 counts hosts matching a Shodan search query, distinguishing it from sibling tools like shodan_search by emphasizing it does not spend query credits. The verb 'count' and resource 'hosts' are specific, and the contrast with 'full search' differentiates it from search siblings.

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 description provides explicit usage context: 'Use this for quick world-scale stats ... before running a full search.' It gives an example (CVE exposure) and implies the alternative of a full search, though it does not explicitly name the sibling tool or state when not to use it in detail.

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