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

Annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the bar is lower; the description still earns credit by disclosing the auth scope (listings:read) and by flagging that each field's limits are included. It adds no rate-limit or freshness/caching notes, but those are minor for a safe read.

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?

Front-loaded with the core claim, followed by one imperative and one auth note — no filler. The middle enumeration of field groups is a long run-on clause that could be tightened, which keeps it at 4 rather than 5.

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 the description need not explain return values; it instead supplies the missing pieces an agent needs: what the payload covers, when to call it, which tool consumes it, and the required auth scope. Nothing material is absent for a zero-parameter reference 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?

The tool takes zero parameters, so the baseline is 4. The description goes slightly beyond by noting options are picked "by slug" and that link kinds come with an example of each, which hints at how returned values should be consumed.

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 names a precise resource — the option catalog that update_listing consumes — and enumerates its contents (categories, technologies, platforms, audiences, tags, pricing models, currencies, price periods, demo video hosts, link kinds, field limits). That enumeration distinguishes it from narrower siblings like list_categories and get_pricing, which cover only a slice of this data.

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?

"Call it before editing so you never guess a value" gives a clear trigger tied to a named sibling (update_listing), and "Needs listings:read" states the prerequisite. It stops short of a full routing statement (no explicit when-not or named alternative for read-only catalog needs), which keeps it below a 5.

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