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

Annotations already flag this as a non-read-only, open-world, non-idempotent operation; the description adds genuinely non-structured traits: the token is short-lived, WebSocket use can incur cost, and the token must never be published. It does not quantify cost or explain revocation/expiry behavior beyond 'short-lived'.

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, each carrying a distinct payload: what it does, the cost risk, and the security constraint. Front-loaded and waste-free.

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 still conveys that a URL/token is returned and that it is sensitive, and it covers the cost side effect. It leaves the exact response shape and the meaning of the required 'id' resource implicit, which is a minor gap for a two-parameter creation tool.

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%, with ttl_seconds and max_duration_seconds fully documented (including clamping ranges) in the schema. The description adds nothing about parameters, which is acceptable given the schema carries the load, but earns only the baseline.

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 opens with a specific verb and resource: 'Issue a short-lived browser voice-test URL.' An agent knows exactly what is produced and for what surface (browser voice test). It does not explicitly contrast with siblings such as create_api_key, but no sibling occupies the same niche.

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?

Clear context for when to use it (browser voice-test session) plus an operational warning that opening the WebSocket can incur usage. There are no explicit exclusions or named alternatives, so it stops short of a full when/when-not statement.

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