IT Tools MCP Server

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

Annotations provide readOnlyHint=false, indicating this is not a read-only operation, which aligns with the description's 'Generate' action implying creation. The description doesn't add significant behavioral context beyond this, such as rate limits, authentication needs, or output format details. Since annotations cover the basic safety profile, the description adds minimal value, warranting an average score.

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 and front-loaded with the essential information: 'Generate HMAC (Hash-based Message Authentication Code)'. It uses a single, efficient sentence with no wasted words, making it easy for an agent to parse quickly. This is an example of optimal brevity without under-specification.

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 tool's moderate complexity (3 parameters, cryptographic function) and lack of output schema, the description is minimally complete. It states what the tool does but doesn't explain return values, error handling, or practical context. With annotations covering basic behavioral hints, it's adequate but leaves gaps in full understanding, aligning with a baseline score.

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 100% description coverage, with clear documentation for 'message', 'key', and 'algorithm' parameters. The description doesn't add any extra semantic details beyond what the schema provides, such as example usage or format constraints. According to the rules, with high schema coverage, the baseline is 3, which is appropriate here as the description doesn't compensate with additional insights.

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's purpose: 'Generate HMAC (Hash-based Message Authentication Code)'. It specifies the verb ('Generate') and resource ('HMAC'), making it easy to understand what the tool does. However, it doesn't differentiate from sibling tools like 'hash_sha256' or 'generate_token', which might have overlapping cryptographic functions, preventing a perfect score.

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. It doesn't mention when HMAC generation is appropriate compared to other hashing or token generation tools in the sibling list, such as 'hash_sha256' or 'generate_token'. There's no context on prerequisites, exclusions, or typical use cases, leaving the agent without usage direction.

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