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

No annotations are provided, so the description carries the full burden of behavioral disclosure. The description is a single sentence with no details about expected output, rate limits, authentication, error behavior, or any side effects. It only states the general function without any behavioral context, making it severely deficient.

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 – a single sentence. It is front-loaded with the core purpose, but it is under-specified rather than efficiently detailed. It could benefit from a few more words to clarify the input and output, so it is not a model of effective conciseness.

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 tool with a single parameter and no annotations, the description is far too sparse. It does not explain the input format, the output structure (even though an output schema exists, the description doesn't reference it), or any constraints. Given the tool's simplicity, a bit more detail would be expected, making this incomplete.

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 has one parameter 'q' with 0% description coverage and no enums or constraints. The description does not explain what 'q' represents (presumably the hash to look up) or its expected format. Since the schema provides no meaning and the description adds nothing, agents cannot infer how to populate the parameter correctly.

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 clear purpose: 'Hash Lookup: Known-file lookup (CIRCL hashlookup)' – it indicates this tool performs a hash-based lookup of known files via the CIRCL hashlookup service. This distinguishes it from generic hashing tools like hashid or hashtext, but it does not specify the hash types supported or the exact nature of the lookup, so it's not fully differentiated from other hash-related tools.

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 provides no guidance on when to use this tool versus alternatives. Given the large sibling list with many hash-related tools (e.g., sha256lookup, hashid, hashtext), there is no mention of when this tool is preferred or what conditions select it. The usage context is completely absent.

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