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

The description lacks behavioral details beyond stating it is a query-like operation. There are no annotations, so the description bears full responsibility. It does not disclose whether the operation is read-only, if results are cached, rate limits, or what happens when no results are found. The mention of 'email IOCs' is unsupported by the schema, adding confusion.

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 extremely concise with two short sentences. The first sentence front-loads the core purpose, and the second sentence adds a memorable metaphor. No unnecessary words or repetition.

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 the lack of output schema and annotations, the description should provide more context about return values, behavior when no match is found, and how results are structured. It does not mention pagination, confirmation of maliciousness, or any other details that would help an agent use the tool effectively in a sequence.

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 input schema already provides clear descriptions for both parameters ('C2 host to check', 'npm package name to check'), achieving 100% coverage. The description adds minimal value by grouping them under the umbrella of 'known-malicious...' but also introduces 'versions' and 'email IOCs' not in the schema, which could mislead an agent. Overall, the schema does the heavy lifting.

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 queries known-malicious MCP packages, versions, C2 hosts, and email IOCs. It uses a specific verb and resource, and the metaphor 'virus database for MCP' reinforces the purpose. However, it does not explicitly differentiate from siblings like cve_search, and mentions 'versions' and 'email IOCs' not present in the schema, causing slight ambiguity.

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?

No guidance is provided on when to use this tool versus alternatives. There are no prerequisites, exclusion criteria, or examples of appropriate use. The description only implies checking package or host names, but fails to mention that both parameters are optional or when to choose one over the other.

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