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

With no annotations, the description fully discloses behavior: it declares 'Synchronous GET with no request body,' itemizes the exact response structure (animations array with fields, deduplicated perspectives, directions list), explains the conditional clip_url field, and states 'does not charge credits.' This goes beyond minimal disclosure and directly answers likely agent questions.

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 front-loaded with the core purpose, then gives response structure, then usage guidance. Every sentence adds value: purpose, response detail, and linkage to sibling tools. It is concise despite being detailed, with no filler.

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?

Given there is no output schema, the description provides a detailed enum of the response fields and the deduplication behavior, which is essential for an agent to parse the result. It also covers cost, call type, and usage examples, making it complete for a no-parameter discovery endpoint.

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?

The input schema is empty (0 parameters), so there are no parameter semantics needed. The baseline for zero parameters is 4, and the description does not attempt to describe nonexistent parameters. It instead focuses on output and usage, which is appropriate.

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: 'List the available animation presets along with their perspectives and the eight supported compass directions (N, NE, E, SE, S, SW, W, NW).' It clearly differentiates from sibling tools by naming transferMotion, animateSprite, and animate3DModelPreset as the tools that consume this data.

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 explicitly states when to use the tool: 'Use it to obtain the preset_id, perspective, and direction values that transferMotion needs, and to find motion preset names you can reference when animating.' It also names alternatives and pairing tools, and mentions the endpoint is free, providing a clear decision factor.

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