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

With no annotations, the description carries the full behavioral burden and does well: it discloses quota requirements, the two-hour sample expiration, and the user-selection prerequisite. It does not describe success/failure behavior or whether saving consumes resources irreversibly, so it stops short of complete transparency.

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 tightly written and front-loads the action before listing constraints. Every sentence adds useful information about selection, prerequisites, or timing.

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 mutation tool with no annotations and no output schema, the description covers the most important operational context: prerequisites, expiration, and when the save is appropriate. It is slightly incomplete because it does not say what is returned or what happens on failure, but the core context is strong.

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 all four parameters are already documented. The description reinforces that sample is 1, 2, or 3 and that preview_id is an alternative, but adds little beyond what the schema already provides.

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 states a specific verb and resource: keep one sample from the last design_voice as the user's own voice under a name. It clearly distinguishes this from design_voice, which creates the samples, and delete_designed_voice, which removes a saved voice.

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 context: this should be used only after the user has listened and chosen a sample, and it requires a free designed-voice slot plus at least 1 Voice Pack minute. It references design_voice as the source but does not explicitly contrast with other related tools or say when not to use this one.

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