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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is fully covered without the description. The description adds only 'Takes no arguments' and a list of return fields, the latter of which is redundant given an output schema exists. Useful but thin beyond structured data.

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 compact sentences with zero filler: purpose and return shape first, then the actionable usage cue. Nothing is padded or repeated.

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 zero-argument read-only catalog tool with a rich output schema and full annotation coverage, the description supplies everything needed: what it returns, why to call it, and that it needs no input. The return-field enumeration is mildly redundant against the output schema but not harmful.

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?

The tool takes zero parameters, so the baseline is 4 and there is nothing to disambiguate. The phrase 'Takes no arguments' correctly reinforces the empty schema, though it earns little extra credit.

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 the voices an AgentOnAir host can use') and immediately enumerates what each entry contains (id, description, preview clip). This clearly distinguishes it from the sibling tools, which are all episode- or launch-oriented rather than voice-catalog-oriented.

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 names the downstream consumers ('Call it to pick a voice id for preview_agent_launch or validate_episode_script'), which tells the agent when this tool is the right prerequisite. It stops short of stating when NOT to use it or what to do if no suitable voice exists, so it is clear context rather than full when/when-not guidance.

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