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

Annotations already declare readOnly, idempotent, non-destructive, closed-world. The description adds context annotations cannot convey: results are alphabetical, catalog coverage only, carry no participation status, and are produced by a payment-blind engine. It does not mention pagination or roster size limits, which keeps it from 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 front-loaded sentences that lead with what the tool returns. Mild redundancy: 'as catalog coverage only' and 'It is catalog coverage, not a ranking' restate the same exclusion twice, costing a little space.

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?

A read-only one-parameter lookup with a rich annotation set and an output schema. The description covers what it returns (roster plus assessment-start URL), what it excludes, and when to call it, leaving no material gap for an agent.

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%, but the single parameter is an enum that already enumerates the five accepted verticals. The description says 'one vertical' but adds no syntax, default, or value guidance beyond the enum, so it neither compensates for the coverage gap nor detracts.

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 ('Lists the vendors PreShiftIQ covers in one vertical') with the scope modifier 'alphabetically, as catalog coverage only.' Clearly separable from siblings like my_matches and list_verticals without opening a schema.

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?

Gives an explicit trigger ('Use this when a user asks which vendors PreShiftIQ covers or whether a named vendor is covered') and implicitly excludes match/ranking questions by pointing to the buyer's own assessment for matches. No sibling is named as a formal alternative, so it stops 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.