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

Annotations already declare readOnlyHint=true, openWorldHint=false, and destructiveHint=false, so the safety profile is covered. The description adds meaningful behavioral context beyond the annotations by specifying the returned coverage details, including syndication, grounding, and the roll-up that includes guides homed to properties without a rendering surface. This gives the agent a concrete sense of what the registry list exposes.

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 dense sentence that front-loads the core action and resource, then efficiently enumerates the meaningful included fields and the notable roll-up behavior. There is no filler, repetition, or unnecessary qualification.

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?

With a complete input schema, an output schema present, and safety annotations already supplied, the description covers the main remaining contextual need: what the registry listing includes and that it surfaces distribution gaps. The tool is a straightforward read-only list operation, and the description is sufficient for an agent to select and invoke it correctly.

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%, so the input schema already documents all 13 parameters with examples and type details. The tool description itself adds no parameter-level meaning, so the baseline of 3 applies. It does not need to compensate for any schema gaps.

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 names the specific resource (bicycle.guide registry) and the action (list), and enumerates the fields included, so an agent can tell this from get_guide, list_capabilities, and list_taxonomy without opening the schema. The scope 'every guide' plus the distribution roll-up makes the tool's distinct purpose unambiguous.

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 makes the listing scope clear, so an agent can infer this is for registry-wide enumeration rather than fetching one guide or listing a different entity type. However, it never explicitly states when to prefer this over get_guide or list_capabilities, or when not to use it. Usage is implied but not directly guided.

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