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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds one genuine caveat beyond that: 'Preparation readiness does not verify live speech', which clarifies the limit of the check. It still doesn't explain what runtime readiness depends on or what statuses might come back.

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 tight sentences, front-loaded with the action and immediately followed by the key caveat. No filler; every sentence earns its place.

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 read-only check with no output schema, the description should ideally describe what a readiness result conveys, and it leaves both parameters undefined. It covers the conceptual distinction (prep vs live speech) but not enough for an agent to interpret the return value confidently.

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 0%, so neither workspaceId nor characterId is documented anywhere, and the description says nothing about either parameter. With low coverage the description is expected to compensate, and it does not.

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 ('Check') and resource ('saved avatar preparation and runtime readiness') and explicitly scopes the tool as not starting a call, which separates it from start_live_avatar_session. It stops short of naming the sibling alternatives (prepare_live_avatar, get_live_avatar) directly.

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 phrase 'without starting a call' implies the use case (inspecting readiness prior to launching a session), but there is no explicit when-to-use/when-not guidance and no routing to related tools such as prepare_live_avatar or get_live_avatar. Usage is implied rather than stated.

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