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

With no annotations, the description must disclose behavioral traits, but it only states the core function. There is no mention of error handling (e.g., invalid hex), output encoding (UTF-8?), or whether leading '0x' is supported. The description is insufficient for the agent to anticipate behavior beyond the basic operation.

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 (three words) with no filler. It front-loads the essential action and resource, making it efficient for an agent to parse. Every word earns its place.

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?

Despite the tool's simplicity, the description lacks information about output format (e.g., plain text, byte representation), handling of uppercase/lowercase hex, or edge cases. An output schema exists but is not described, leaving the agent uninformed about return values.

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 coverage is 100% (the single parameter is fully described as 'Hex string to decode'). The description adds no additional meaning beyond what the schema already provides, so it meets the baseline but does not enhance clarity.

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 action ('decode') and the resource ('hexadecimal to text'), making the tool's purpose unambiguous. It distinguishes from sibling decoding tools (e.g., base64_decode, ascii_decode) by specifying the source format as hexadecimal.

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 like hex_encode or other decoders. The description assumes the agent knows when decoding is appropriate, with no conditions, prerequisites, or exclusions.

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