物理ランタイム状態取得

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

The description adds significant behavioral context beyond the readOnlyHint annotation: it discloses that velocity is zero in Editor, grounding is false, and RigidBody absence affects velocity. No contradictions.

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 concise (3 lines) with front-loaded purpose, uses visual markers (★) for important notes, and includes necessary behavioral caveats without unnecessary content.

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?

Despite the output schema being external, the description lists the return fields inline, making it self-contained. It addresses state dependencies (Playing vs Editor) and entity requirements, providing a complete understanding.

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 coverage is 100%, and the schema already describes both parameters with clear descriptions. The description merely restates that entity can be specified by id or name, adding no new semantic value beyond 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 it reads physics runtime state (velocity, ground contact) and lists the returned fields. The tool name and title support this purpose, and it is distinct from sibling getters like get_anim_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?

The description explicitly notes that results are meaningful only during Playing, and explains fallback behavior (no RigidBody leads to zero velocity). It does not directly compare with alternatives but provides sufficient context for appropriate use.

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