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

Annotations already declare readOnlyHint, openWorldHint and non-destructive behavior, so the description only needs to add scope. It does: results are explicitly public reference records, not user-owned data. It does not mention result size, pagination, or what an empty result means, which keeps it short of a 5.

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 short sentences, front-loaded with the purpose, then the exclusion with its alternative, then the parameter preference. No filler and nothing repeated from the schema.

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 values need no explanation, and the read-only, public-only nature is covered. Only pagination/limit behavior and the empty-result case are unaddressed, which is a small residual gap for a search tool.

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 coverage is 83%, so the baseline is 3, and the description adds real selection guidance beyond the schema: prefer facet-specific fields over q when the user names a known facet. It does not address limit or its default, but that gap is minor given the schema.

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 and resource ('find public daylily cultivar reference records') and enumerates the searchable facets (name, hybridizer, color, parentage, general text), which distinguishes it from daylily.get_cultivar and listing-oriented siblings.

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?

Explicit when-to-use, an explicit when-not ('a signed-in user's own inventory'), and the named alternative (daylily.list_listings). It also encodes a routing rule between the broad q parameter and field-specific filters.

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