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

Annotations already provide readOnlyHint=true and openWorldHint=false. The description does not add any new behavioral traits beyond what the annotations convey. It neither contradicts nor enhances the behavioral profile, so a baseline score of 3 is appropriate.

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 a single, concise sentence that is front-loaded with the key action. Every word earns its place, and there is no unnecessary detail or verbosity.

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 simplicity (two parameters, no output schema), the description is mostly complete. It lacks a hint about the return format (e.g., what the documentation looks like), but the annotations and schema cover the rest. Slightly incomplete but still adequate for an agent.

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?

Schema description coverage is 100%, and the existing schema descriptions for opcode and instruction_set are clear. The tool description does not add any additional meaning or context for the parameters, so the baseline score of 3 applies.

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 'Look up documentation for an assembly instruction' clearly states the verb ('look up') and resource ('documentation for an assembly instruction'), distinguishing it from sibling tools that deal with compilation or URL generation. It is not a tautology since it adds specificity over the tool name.

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 explicit guidance on when to use this tool versus alternatives, nor does it mention exclusions or prerequisites. Usage is implied by the purpose, but no explicit 'when-to-use' or 'when-not-to-use' context is provided.

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