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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered and the description can't be faulted for omitting it. The description adds a small amount of context by framing the result as filter values, but says nothing about pagination, ordering, or whether the set is static per catalog.

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 short sentence fragment with no padding, so there is no wasted text. It is under-specified rather than bloated, and the key relational hint (filtering list_library_exercises) is placed up front.

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 no parameters, no output schema, and annotations covering the safety profile, the remaining burden is disambiguating this from list_equipment and confirming it returns a static option set. The description does neither, leaving a meaningful gap for a tool with an almost-identical sibling.

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 takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description does not introduce any confusion about inputs either.

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 identifies the resource (equipment) and ties it to filtering list_library_exercises, but never states a verb or that it returns a list of options, despite the name being list_library_equipment. It also fails to distinguish this catalog-style tool from the sibling list_equipment, which an agent could easily confuse it with.

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?

"Used to filter list_library_exercises" implies the use case: fetch these values when you want to narrow an exercise search. However, there is no explicit when-to-use phrasing, no mention of list_equipment as the alternative for gym-owned equipment, and no guidance on whether this must be called before list_library_exercises.

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