get_node_motion

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

The readOnlyHint annotation already signals safety, and the description adds useful edge-case context: returns motion: null for nodes without Motion, and playheadPosition only in the Design editor with an active timeline. This goes beyond the annotation without contradicting it.

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?

Four sentences densely pack purpose, timing, return shape, and edge cases without filler. The structure is logical: what it reads, when to call, what it returns, and when special fields appear. 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?

Despite no output schema, the description provides a concrete return structure and covers the two main edge cases (motion: null, conditional playheadPosition). For a single-parameter read tool, this is complete enough for an agent to invoke correctly and interpret results.

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 already documents nodeId with 100% coverage, so the description adds little about the parameter itself. It repeats the return object shape including nodeId, but this is output semantics, not added input meaning. Baseline 3 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 clearly states the tool reads a node's Figma Motion state and enumerates specific data components (animationStyles, animations, manualKeyframeTracks, timelines). It distinguishes itself from sibling mutation tools by framing this as the discovery/read operation, and its 'Call it before editing' guidance reinforces its role.

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 says to call it before editing to discover styleIds, timelineIds, and existing keyframes. It also explains when the playheadPosition return is meaningful (when the user means 'here'). It doesn't name alternative tools, but the situational guidance is clear.

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