set_selections

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

With no annotations provided, the description carries the burden of behavioral disclosure. It does disclose two behaviors: setting the selection and scrolling the viewport. However, it does not state whether the selection replaces an existing one, what happens if nodeIds are invalid, or any permission requirements. These are moderate gaps for a mutation tool.

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 a single, front-loaded sentence that clearly communicates the core action and the side-effect. It contains no unnecessary words and earns every word's 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?

For a tool with one parameter, no output schema, and no annotations, the description adequately covers the main purpose and the viewport scroll. It is complete enough for an agent to understand how to invoke it, though it could optionally note whether the selection replaces any existing one or if there are constraints on the node IDs.

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 fully describes the single parameter nodeIds as an array of node IDs. The description adds the context that multiple nodes are selected and that the viewport scrolls, but does not add format or semantic details beyond what the schema already provides. Baseline 3 is appropriate given 100% schema 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?

The description uses a specific verb ('Set selection') and clearly names the resource ('multiple nodes in Figma'). It also mentions the secondary behavior of scrolling the viewport, which adds clarity. This clearly distinguishes it from the sibling tool 'get_selection'.

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?

The usage context is clear: this tool changes the current selection in Figma, and the viewport scroll is a helpful side-effect. There are no explicit alternatives mentioned, but the purpose is self-evident. It lacks explicit when-not conditions, but for a simple setter tool, the context is sufficient.

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