animate_image

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

Despite no annotations, the description discloses key traits: async polling, cost per second, duration range, Bitcoin Lightning payment, no API key needed. Lacks details on failure modes or image constraints, but covers major aspects.

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, each providing distinct value: purpose, async nature, cost, and payment. No redundant or vague statements; 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 purpose, inputs, prerequisites, async behavior, cost, and duration. Lacks output format details (no output schema) and potential error conditions, but sufficient for an async tool with polling.

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 already has 100% description coverage; the tool description adds value by explaining payment flow (create_payment with toolName) and duration range. This extra context aids the agent beyond the schema.

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 clearly states the tool converts a still image to video with text guidance, using a specific model. It distinguishes from siblings like generate_video by specifying 'animate a still image' and preserving source fidelity.

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: async behavior, prerequisite create_payment, and payment method. Does not explicitly list when not to use or alternatives, but the context is sufficient for typical usage.

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