Count search results

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

Annotations already declare read-only, idempotent, non-destructive behavior, so the bar is lower. The description nonetheless adds two non-obvious behavioral facts: no query credits are consumed and no host records are returned, both of which materially affect how an agent budgets calls.

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, front-loaded with the outcome, then the constraints, then the usage directive. No filler and nothing buried.

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 2-parameter read tool with full annotation coverage and no output schema, the essential facts (cost, return nature, ordering relative to search) are present. The gap is query and facet syntax, which an agent still has to guess.

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%, so the description must carry parameter meaning, but it only names 'query' and 'facets' without explaining query syntax (Shodan filters), facet format (comma-separated list), or expected values. Optionality of facets is already conveyed by the schema's required list.

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 precise verb+resource: return how many banners match a query, plus facets. It also delimits scope by saying it does not return hosts, which cleanly separates it from shodan_search.

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?

"Use this before shodan_search" gives an explicit sequencing rule and names the sibling alternative. It stops short of covering other alternatives such as shodan_search_facets or when to skip counting entirely, so it is clear but not exhaustive.

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