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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context beyond them: it works WITHOUT an API key (an auth prerequisite the annotations cannot express) and it returns credit costs and marketplace domains. It does not discuss rate limits or response size, but the no-key note is the important one.

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 tight sentences plus a short final clause. The discovery purpose and the no-API-key fact are front-loaded; nothing is padded or 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-value detail is unnecessary. The description covers the discovery role, the auth-free invocation, and the extra marketplace-domain output — everything an agent needs to decide to call it first. No meaningful gap remains.

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 100% and the single optional 'operation' enum parameter is fully documented in the schema, including that it returns a single usage guide instead of the whole catalog. The description alludes to 'their parameters, credit costs, and example use cases' but never mentions the operation filter, so it adds nothing beyond the schema. Baseline 3.

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: list all Easyparser operations with their parameters, credit costs, and example use cases. It is clearly distinguishable from every sibling (which are per-operation data tools) because it describes itself as the catalog/discovery endpoint. The extra disclosure of marketplace domains further pins down scope.

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 explicit when-to-use conditions: 'call this first to understand what the server can do' and 'when you are unsure which tool fits the user's question'. This is precisely the routing guidance an agent needs to pick this meta-tool over the 16 operation-specific siblings.

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