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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false. The description goes beyond that by disclosing the cost model ("Free") and the shape of the returned payload (price, input schema, a free example input), which is genuinely useful since there is no output schema. It does not mention rate limits or result pagination.

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?

Three short sentences, front-loaded with the most decision-relevant fact ("Free") and then the capability, the return shape, and the follow-up action. No sentence is filler and the workflow is readable in one pass.

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 does the work of describing returns (price, input schema, sample input), and annotations carry the safety profile. The only real gap is the undocumented limit parameter and the absence of any note on result ranking or result count. Everything an agent needs to make the call is otherwise present.

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 only 50%: query is documented as "What you need, in a few words" while limit carries only default/min/max bounds and no prose. The description compensates by giving four concrete query phrasings that show the expected granularity. The limit parameter's purpose (result count) is still left to the schema bounds.

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 (Search) plus the resource (all 127 agentsvc.io services) and the axis of search (by task), with concrete query examples. It also positions itself against siblings by naming call_service as the downstream step, so an agent can tell it apart from the concrete task tools like audio_transcribe or token_verdict.

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?

The description clearly establishes the use context: discover a service here, then invoke it with call_service. That routing is explicit. It stops short of stating when NOT to use it (e.g. when the exact service tool is already known), so it is clear context without full exclusion guidance.

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