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

Annotations already declare readOnlyHint, idempotentHint, and closed-world behavior, so safety is covered. The description adds value by disclosing that the result is a physics-simulated state vector across a timeline and that it is not an analytical/symbolic solution — context the annotations do not provide. It stops short of noting computational cost or determinism.

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?

Two dense sentences with no filler; the core operation is front-loaded before the scope caveat. Every clause carries information about behavior or constraints.

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 whose input includes a nested, undocumented 'document' object and which has no output schema, the description does describe return contents well. But it never explains what 'document' is or how it should be obtained (presumably from a scene-building sibling), leaving a notable gap for correct invocation.

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 75%, so most parameters are documented in the schema (duration, sampleInterval, bodyIds constraints). The description only adds '参数需为数值', which is somewhat imprecise since bodyIds is an array of string IDs, and it does not clarify the opaque 'document' parameter. Baseline 3 is appropriate.

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+resource: it reuses the planar physics engine and parameter timeline to analyze motion state, and enumerates the returned quantities (position, velocity, acceleration, force, contact, spring state, sampling stage). Purpose is clear, though it does not explicitly contrast itself with scene-building siblings such as build_scene or inspect_scene.

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 provides a scope boundary ('不是符号求解或无限时域的完整解析解') that tells the agent when this tool is NOT appropriate, which is useful. However, it gives no positive 'when to use' trigger nor names an alternative sibling for comparing motion vs. static inspection.

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