What a component exposes

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

Beyond the readOnlyHint and destructiveHint annotations, the description discloses the key-format behavior ("Label#8:2", not "Label") and that the tool returns current instance values. This surfaces a non-obvious quirk an agent would otherwise only discover after a failed call.

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 tightly written: the first sentence defines scope and output, the second gives essential sequencing and the key-format warning. No filler or redundant restating of the tool name appears.

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?

With no output schema, the description carries the burden of explaining what the tool returns, and it does: it lists the property kinds and current values. It also provides the crucial prerequisite relationship to the setter, making the definition complete for correct invocation.

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 single nodeId parameter is already fully documented in the schema, including the optional behavior of using the current canvas selection. The description adds no additional parameter-level meaning, so the 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 names a specific verb and resource: it retrieves the properties of a component, component set, or instance, enumerating variants and text, boolean, and instance-swap properties. This clearly distinguishes it from siblings like figma_get_tree and figma_set_instance_properties.

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 instructs the agent to call this tool before figma_set_instance_properties, and explains why: the setter requires keys with an id suffix that cannot be guessed. This is direct, actionable usage guidance tied to a concrete sibling.

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