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

No annotations are provided, so the description must carry the behavioral burden. It usefully discloses that the tool is paid (0.001 USDC on Base via x402) and that the output is a hex digest, but it omits authentication details, rate limits, error behavior, and default algorithm behavior.

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 two tight sentences: purpose first, then arguments and algorithms, then payment details. Every sentence carries relevant 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?

For a simple hashing utility, the description covers the purpose, argument names, algorithm choices, output format, and payment requirement. It lacks details such as default algorithm and error handling, but those gaps are minor for this tool complexity.

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 is a generic object with only additionalProperties and no named properties, so the description adds substantial meaning by naming the arguments 's' and 'alg' and enumerating the allowed algorithm values. It does not state whether 'alg' is optional or what the default is, which keeps it from a 5.

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 operation and resource: 'Hex digest of a string.' It also lists supported algorithms, which helps distinguish it from encoding-oriented siblings like base64 and uuid, though it does not explicitly contrast with them.

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?

There is no guidance on when to use this tool versus alternatives such as base64, uuid, or the other utility siblings. The description only lists the arguments and payment requirement, leaving usage selection entirely to inference.

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