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

With no annotations, the description carries the burden and discloses important behavioral details: paid calls at $0.005 USDC per call via x402 and a free 3-row preview via sample=true. It does not cover return shape, pagination behavior, or error handling, but the payment and preview constraints are the key non-obvious traits.

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?

The description is dense but front-loaded and largely earns its space by packing purpose, use cases, route parameters, payment, and preview into a compact block. The semicolon-separated route list is information-rich but slightly hard to scan.

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?

Given the multi-route complexity, lack of annotations, and no output schema, the description adequately covers routes, key parameters, payment, and sample mode. However, it leaves gaps around response structure, pagination, allowed route parameter values, and error behavior.

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%, so the baseline would be 3, but the description adds meaningful route-specific parameter mappings such as /nearby needing lat*, lon*, kind, and form, and /nonprofits/search supporting revenue and cause filters. It still does not define allowed values or formats for many fields like kind, form, or sort.

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 clearly defines the resource as a world directory of organizations such as research bodies, societies, funders, and publishers, explicitly excluding companies and governments. The route list makes the available operations concrete, so an agent can distinguish this tool from sibling datasets like airports, regions, or markets.

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?

It gives clear usage contexts including research tools, grant finders, CRM enrichment, maps, education apps, and AI agents, and notes that the directory excludes companies and governments. It does not explicitly compare against alternative sibling tools or give when-not-to-use guidance, but the tool-level usage context is clear.

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