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

The pricing disclosure, free-endpoint exceptions, and cost warning are valuable behavioral details beyond openWorldHint. However, supporting arbitrary endpoints and task_post operations can create remote tasks and incur billable side effects, which conflicts with readOnlyHint=true; this annotation contradiction overrides the otherwise useful disclosure.

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 compact sentences front-load the tool's fallback role, then cover the API contract, billing, and cost controls. The example list is dense but useful for endpoint discovery, and there is no filler.

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?

For a broad API proxy, the selection rule, documentation link, schema-supplied method mapping and path example, and cost safeguards cover most invocation needs. Task lifecycle, polling, and error behavior remain delegated to external documentation, and the read-only metadata conflict prevents full confidence in safe invocation.

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 description coverage is 100%, so the baseline is 3. The documentation link and instruction to include a limit or filters add practical guidance for constructing body task objects, although the description provides no concrete payload example.

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 uses a specific verb and resource—calling DataForSEO v3 endpoints directly—and positions the tool as a general fallback when no dedicated tool fits. Concrete examples such as Google Maps, Google Trends, WHOIS, and task endpoints communicate its breadth and distinguish it from the dedicated sibling tools.

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 explicitly says to use this tool when no dedicated tool fits, directing agents toward specialized siblings when available. It also distinguishes free task_get and tasks_ready calls and instructs agents to always set a limit or filters to avoid expensive requests.

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