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

Beyond the readOnlyHint/openWorldHint annotations, the description discloses two meaningful traits: a hard result cap ('Up to 10 frequency rows per call') and the billing model ($0.002 USDC per successful call via x402 on Base/Solana/Arc, failures not charged). That is real operational context an agent needs before calling. It stops short of describing rate limits or what a not-found rs id returns.

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?

Two sentences, no filler: the data payload is front-loaded and the cost/result-cap sentence follows. Slightly compressed — the pricing clause bundles currency, rails, and failure policy into one dense phrase, but nothing is wasted.

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?

For a single-parameter read tool with an output schema and read-only annotations, the description covers the essentials (data returned, result cap, cost model). The main residual gap is error behavior for invalid or unknown rs identifiers, which matters for a paid per-call endpoint.

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?

Only one parameter and schema coverage is 100%, with the schema itself supplying the rs-number format and an example (rs429358). The description adds no additional constraint or format guidance for rsid beyond restating 'by rs number', so the baseline of 3 applies.

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?

States a specific verb+resource: retrieves the NCBI dbSNP short variant record for an rs number, and enumerates exactly what the record contains (variant type, sequence placement, ref/alt alleles, allele frequencies). This is clearly distinguishable from genomic siblings like health_clinvar_genetic_variants or health_gwas_catalog_associations, which the dbSNP naming and field list set apart.

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?

Usage is only implied by the field list (you'd call this when you need variant identity and population allele frequencies). There is no explicit when-to-use statement, no guidance on choosing dbSNP over ClinVar/GWAS Catalog, and no exclusions or prerequisites for the rs-number lookup other than the modifier 'short variant'.

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