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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new context about the payload — 68 entries, each with a description, a free/plan designation, and a launch link — which is valuable given there is no output schema.

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?

A single sentence, front-loaded with the verb and the exact count, then the three fields returned. The parenthetical example list is slightly long and trails into an ellipsis, but nothing is redundant enough to waste an agent's attention.

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?

With no output schema, the description carries the burden of describing return values, and it does so — per-tool description, free/plan status, and link. It could note that the catalog is static or that plan labels may change, but for a zero-parameter read tool this is sufficient to call 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?

The tool takes zero parameters, so the baseline is 4. The description correctly implies a single unfiltered call that returns the full catalog, which is consistent with an empty input 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 (list) and resource (all 68 single-purpose tools) and immediately enumerates the kinds of tools covered, so an agent knows exactly what category of content this returns. It does not explicitly differentiate itself from the closest sibling, get_pricing, which also carries plan information.

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 implied rather than stated: an agent can infer this is the catalog-lookup tool for discovering tools and their plan requirements. There is no explicit when-to-use framing and no mention of get_pricing as the alternative for detailed pricing tiers, so a routing decision against siblings is left to inference.

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