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

Annotations already cover safety (readOnlyHint=true, openWorldHint=false), but the description adds genuinely non-obvious behavioral facts: positions are schematic rather than measured and there is no GPS, and court colour is an activity marker rather than a reputation signal. These prevent the agent from misreading the payload. It does not discuss freshness/caching or the exact response envelope, keeping it below a 5.

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?

Front-loaded with the verb and object, then a colon list of contents, then two caveat clauses — no filler. The single sentence is dense and could have been split for readability, which keeps it from a 5.

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 parameters, no output schema, and covering annotations, the description carries the remaining burden and does it: it describes the scene's composition, the data values attached to nodes, and the interpretation caveats. Only the exact return structure/format is left implicit, which is a minor gap for a zero-argument read 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?

The tool takes zero parameters and the schema confirms an empty, closed object, so there is nothing for the description to disambiguate. Baseline 4 applies; no parameter documentation is owed here.

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 and resource ('Returns a schematic 3D scene of the Orb Studio node') and enumerates exactly what is in it: nodes (EMO robot, violin, court activity, agent visits) arranged on a circle around a centre, with status values and today's violin score points. That enumeration is what separates it from siblings like get_violin (scores only) or emo_robot (single-device state).

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 names its audience/context ('for AR/VR headsets and spatial agents'), which implies when it is appropriate, but there is no explicit when-to-use versus when-not guidance and no sibling is named as an alternative. An agent must infer that this is the spatial-view counterpart to get_violin and emo_robot.

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