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

Annotations already declare read-only/non-destructive, so the description needs to add output behavior. It does mention the distribution roll-up and the no-rendering-surface edge case, but it presents full-row fields and roll-up as unconditional while the schema default for fields is 'compact', which omits rollup/registry_meta and several listed fields. That makes the behavior description misleading for default calls.

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?

A single front-loaded sentence with no filler; the verb and object come first. The long dash clause is dense but relevant, though it would be tighter if it noted the fields=full dependency.

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 13 optional filters, full schema coverage, and an output schema, the structured data already provides most context. The main gap is that the description's roll-up/full-row promise conflicts with the default compact row shape, so an agent must read the fields parameter to avoid expecting output the default call will not return.

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?

All 13 parameters are described in the schema, so the baseline is 3. The description does not add parameter-level meaning; it mostly recaps output fields, which is fine because the schema carries the parameter documentation.

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 opens with a specific verb and object, 'List the bicycle.guide registry', and clarifies breadth ('every guide') plus the included fields. This cleanly separates it from singular get_guide and from list_capabilities/list_taxonomy.

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 registry-scope wording implies using this when you need the whole guide list rather than a single guide or another taxonomy. It never names alternatives or exclusions explicitly, so it stops short of a 5.

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