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

Beyond the read-only, idempotent, and non-destructive annotations, it discloses the heuristic detection approach, low/medium/high risk classification, daily free-call limit, subsequent pricing, and HTTP endpoint or API-key credit options. These details help the agent anticipate both the nature of the assessment and invocation costs.

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 operation and applicable content are front-loaded, followed by detection categories, risk levels, and quota or payment details. The compact phrasing contains substantial actionable information without filler.

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 single-parameter scanner with complete annotations and an output schema, the description covers scope, method, representative threats, result granularity, and usage costs. It provides enough context for correct selection and invocation without needing to explain the structured return value.

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 schema already fully documents the single required "text" parameter as untrusted text. The description adds useful source context by identifying web, email, and tool content, although it supplies no additional size or preprocessing constraints.

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 pairs the specific verb "scan" with untrusted web, email, and tool content, then enumerates concrete injection markers. This clearly distinguishes it from general text-analysis and other security-related 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?

It gives clear usage context: apply the heuristic scanner to untrusted web, email, or tool content when checking for prompt injection. It does not provide explicit when-not guidance or name alternatives for adjacent tasks such as PII redaction or token safety checks.

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