get_variant_credible_sets

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

Annotations declare readOnlyHint: true, so the agent knows it is a safe read operation. The description adds minimal behavioral context beyond that, such as the filtering by variant, but does not mention pagination, return format, or other traits. It does not contradict annotations, and with annotations covering the safety profile, a 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, clear sentence with no wasted words. It directly states the purpose without filler, scoring high on conciseness and structure.

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 four parameters, an output schema, and read-only annotation, the description is too brief. It does not explain pagination (page_size/page_index), the optional study_types filter, or any details about the response. While the output schema exists, the lack of usage context makes the tool difficult to invoke 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 0%, so the description must compensate. The description only implies the role of variant_id ('specific variant') but provides no meaning for page_size, page_index, or study_types. This leaves significant gaps for the other three parameters.

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 'List credible sets that include a specific variant' uses a specific verb ('List') and resource ('credible sets') with a clear filter (specific variant). It distinguishes from sibling tools like get_credible_sets (all sets), get_study_credible_sets (by study), and get_credible_set_by_id (by ID).

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?

No explicit when-to-use or alternative exclusions are provided. The usage is implied: when you have a variant and want the credible sets containing it. The description gives clear context but does not mention when not to use it or point to alternatives, so it falls at the 'implied usage' level.

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