Create shapes with text

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

With no annotations, the description must carry the burden of behavioral disclosure. It states the core behavior (adds shapes with text labels) and its contextual role, but does not mention permissions, side effects, or return values. Since it is a creation tool, the add-only behavior is somewhat implicit, but richer context would improve transparency.

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 two sentences, front-loaded with the action, and includes a clear distinction from a sibling tool without redundancy. Every sentence adds value, making it highly concise and well-structured.

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?

The description effectively conveys purpose and usage, and the rich input schema fills in parameter details. However, with no output schema and no annotations, the description omits what the tool returns after creation and does not mention constraints like the 200-item maximum or coordinate behavior. This leaves gaps for an agent trying to fully predict tool behavior.

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 tool description contains no explanation of the 'items' parameter or its structure, even though schema description coverage is 0% at the top level. Although the nested schema has detailed descriptions for each field, the description does not compensate for the low coverage, leaving the agent to infer the array-of-shapes structure solely from 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's action ('Add FigJam shapes that carry a text label') and resource, and differentiates it from the sibling create_diagram by specifying that create_diagram lays out and connects shapes. This makes the purpose unambiguous and distinguishes from alternatives.

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 description explicitly recommends using create_diagram for whole diagrams, providing a clear when-not-to-use scenario and an alternative. While it implies using this tool for individual labeled shapes, it does not explicitly enumerate all when-to-use cases beyond the building-block context.

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