biothings_get_variants

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

With no annotations, the description carries full burden. It states retrieval of annotation data and input format, but omits behaviors like required authentication, rate limits, handling of invalid IDs, or maximum number of variants per request. Output schema exists but description doesn't hint at response structure. Gaps in behavioral context.

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?

Description is relatively short and front-loaded with the core purpose. Uses bullet-style formatting for examples. Could be slightly more concise by removing redundant phrasing, but overall efficient.

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?

Given the output schema exists, return values need no explanation. However, the description lacks details on the optional parameters (`email`, `fields`) and does not discuss behavior limits or error handling. The variant_ids parameter is well-covered, but the tool's overall context is incomplete for a tool with 3 parameters and no annotations.

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 description must compensate. It thoroughly explains the `variant_ids` parameter format with examples, but provides no information on `email` or `fields` parameters. Adds meaning beyond schema only for one of three parameters, leaving others undocumented.

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 clearly states 'Fetch multiple variants by a comma-separated list of HGVS or rsIDs', specifying the verb and resource. It distinguishes itself from the sibling tool `query_many_variants` by noting it is preferred when standard IDs are known, providing strong differentiation.

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?

Explicitly says 'This is the preferred tool over query_many_variants for fetching multiple specific variants when you already know their standard IDs (HGVS or rsID).' This gives clear guidance on when to use this tool versus the alternative, and includes input format examples.

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