Render a design

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

Annotations already declare readOnlyHint=true, and the description is consistent with a safe read operation. It usefully adds that the optional step is 1-based and that newly added parts are highlighted and labelled, but says nothing about the return medium (image data vs URL) or rendering cost, which matters with no output schema.

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?

A single well-formed sentence that front-loads the core action and packs the step semantics and highlight behavior into the remainder. No filler or redundancy.

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 should say what the caller receives (image bytes, URL, file path), but it leaves the return value unspecified. Combined with the undocumented design_id, the definition is adequate but incomplete for a two-parameter rendering tool.

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?

Schema description coverage is 0%, so the description carries the burden for both parameters. It explains step well (1-based index selecting a single assembly step) but never clarifies design_id, leaving half the parameters undocumented in both schema and prose.

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?

States a specific verb (render) and resource (isometric preview of the finished piece or a single assembly step) plus the distinguishing behavior of highlighting and labelling newly added parts. An agent can differentiate this visualization tool from siblings like aikea_get_design or aikea_build without opening the schema.

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 implies usage (call it to visualize a design or a build step) but never states when to choose this over alternatives such as aikea_get_design or aikea_build, nor any preconditions like requiring the design to already exist. Guidance is inferable but not explicit.

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