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

The description reveals that results are candidate endpoints with summaries and a `scoped_to_curated` boolean, and explains how to interpret zero results when the boolean is true. This adds concrete open-world semantics on top of the openWorldHint annotation. There is no contradiction with readOnly or destructive hints.

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?

Four sentences, all high signal and front-loaded: scope, usage condition, return summary, and next action. No filler or redundancy. It is as compact as the content allows.

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?

The workflow is complete: when to call, what it returns, how to interpret open-world zero results, and what to do next. With no output schema, the return description is sufficient for an agent to decide whether to proceed. The only meaningful gap is the undocumented `limit` parameter, which is a minor omission.

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?

With 0% schema description coverage, the description must compensate; it does for `query` by noting capability/name search and giving an example. However, the optional `limit` parameter is not described at all, so the agent is left to infer whether it caps result count or controls pagination. This is a partial compensation, not a full one.

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 action and scope: 'Search the full ApyHub API catalog by capability or name', with a concrete example. It also differentiates itself from curated_apis by saying to use it only after that sibling fails. This gives the agent a clear sense of the tool's role.

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?

Explicitly says 'Only use this if curated_apis didn't have what you need,' which sets the condition for choosing it over the sibling. It also tells the agent to follow up with get_api_spec before invoking the endpoint. No alternative is missing.

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