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

With no annotations, the description carries the full behavioral burden. It usefully discloses per-scan pricing and a shared free tier, but it does not explain permissions, data retention, failure behavior, or rate limits beyond the cost note.

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 front-loaded with the core purpose and return values, followed by concise pricing details. Every sentence contributes useful information with no wasted wording.

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?

The description plus the existing output schema and complete input schema give enough information to invoke the tool correctly. It still lacks explicit routing guidance versus read_url and some operational details, but those are minor for a one-parameter scan tool.

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 has 100% description coverage for the single text parameter, so parameter meaning is already clear. The tool description adds no syntax, format, or semantic detail beyond what the schema provides.

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 states a specific verb and resource: scan text for prompt-injection risk. It also specifies the return shape (risk level, score, signals), making it clearly distinct from the sibling read_url tool.

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?

Usage is implied by the purpose, but there is no explicit when-to-use guidance, no when-not-to-use conditions, and no direct comparison to read_url. The pricing and free-tier statements provide cost context but not invocation guidance.

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