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

Annotations already mark this as read-only and non-destructive. The description adds useful behavioral context beyond annotations by noting the data is returned 'as machine-readable data rather than prose' and that shelves include 'live guide counts', which indicates dynamic, computed values.

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 well-structured sentence that front-loads the resource name and immediately enumerates the included data elements. Every phrase adds value, including the 'machine-readable data rather than prose' clarification.

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 zero-parameter read-only tool with an output schema and clear annotations, the description is complete. It tells the agent exactly what data will be returned, covering the taxonomy components and conventions without unnecessary detail.

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 tool has zero parameters, so the schema imposes no burden. The description does not need to explain parameters, and the baseline of 4 applies because there is nothing missing.

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 uses the specific verb 'Get' with a clear resource, 'bicycle.guide vocabulary', and enumerates the exact contents: domains, shelves, series, personas, guide_types, and classification conventions. This makes it easy to distinguish from siblings like list_guides and list_capabilities, which target different resources.

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 implies this tool is for retrieving the taxonomy/vocabulary rather than individual guides or capabilities, but it does not explicitly state when to prefer this over list_guides, get_guide, or list_capabilities. No exclusion criteria or alternative routing is provided.

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