Look up drug-gene guidance

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), yet the description adds real context: only gene and drug names are transmitted (privacy), the source hierarchy (CPIC/DPWG, else drug label or primary literature), and a clear educational/non-prescriptive disclaimer.

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?

Three sentences, front-loaded with purpose and scope, with no filler. The middle clause enumerating guideline sources is dense but earns its place; overall slightly long for the payload.

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?

An output schema exists, so return structure need not be re-explained. The description still covers the source hierarchy, the privacy of transmitted data, and the educational caveat — everything an agent needs to call 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 both parameters are already documented in the schema; the description's 'optionally for one drug' only mildly reinforces optionality. With the schema doing the heavy lifting, this is the expected baseline.

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?

Specific verb+resource ('Cited pharmacogenomic guidance for a gene, optionally for one drug'), names the data source (DeepDNA public API), and states what is returned (guideline, summary, sources). It also distinguishes itself from the sibling read_dna_file by warning against inferring phenotype groups from that tool's counts.

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?

Clarifies that the drug parameter is optional and gives explicit cross-tool guidance ('do not place the user in one from read_dna_file counts') plus a scope boundary ('educational information, not a dose or a prescription'). It does not spell out a full when-to-use/when-not-to-use decision rule, so it falls 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.