Generate talking avatar

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

Discloses blocking behavior, credit cost, and required capability beyond what annotations (which only indicate non-read-only, non-idempotent) provide. Annotations set a low baseline; the description adds valuable operational context.

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 sentences, no wasted words. Front-loaded with the main action, followed by key behavioral notes. Highly efficient.

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?

Covers main aspects: input, output type, blocking, cost, and prerequisites. However, it omits details on output format, error handling, or script length limits. Given the complexity of avatar generation, this is fairly complete but not exhaustive.

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?

Input schema covers 100% of parameters with adequate descriptions. The tool description adds no additional parameter meaning beyond what the schema already provides, so score is at baseline for high coverage.

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?

Description explicitly states it renders a talking avatar lip-sync clip from a portrait image and script. The verb 'render' and resource 'talking avatar' clearly differentiate it from sibling tools like generate_image (static images) and generate_voice (audio only).

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?

Provides clear context: blocks for 1-3 minutes, requires avatar capability, and spends credits. However, it does not explicitly state when to avoid this tool or suggest alternatives for simpler avatar generation.

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