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

Annotations already establish readOnlyHint, idempotentHint, and openWorldHint, so the description need not re-state safety. It adds meaningful behavioral context by listing the per-host return fields (ip, matched services, location, autonomous system), which is not in the annotations or schema. This clarifies what an agent can expect from the search results.

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 compact and front-loaded with the core action, followed by return fields and an illustrative example. The example is somewhat redundant with the schema's examples, but it is useful and not verbose. It earns its place by showing a realistic invocation.

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 there is no output schema, the description partly compensates by explicitly stating the return fields per host. It also provides a usage example and the query language context. It does not cover error handling or rate limits, but for a read-only search tool with strong annotations and a complete input schema, the remaining gaps are minor.

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%, so the baseline is 3. The description's mention that q is a CenQL query and its example format corroborate the schema without adding genuinely new semantic detail. No parameter information beyond the schema is provided, so the score remains at the baseline.

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 a specific verb ('Search') and resource ('Censys hosts'), and clarifies the scope with 'internet-facing hosts matching a Censys query (CenQL)'. It distinguishes itself from potential siblings like censys_cert_search by naming a different resource, but it does not explicitly call out any sibling tool in the description.

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 implies the primary usage — search hosts by CenQL — but provides no explicit guidance on when not to use this tool or when to prefer alternatives such as censys_cert_search or censys_host. The example demonstrates a valid call, yet there is no exclusionary or comparative instruction to help an agent route correctly.

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