read_quaternion

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

With no annotations provided, the description carries the burden of explaining behavior. It does disclose that the tool reads data and returns quaternion components (w, x, y, z), which is useful. However, it does not mention error behavior, coordinate frame, normalization, or any side-effect assumptions beyond the 'read' verb.

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 and front-loaded with the essential action and result. The opening sentence conveys the core information; the follow-up about gimbal lock adds useful context. The trailing 'Returns' block is slightly redundant with the parenthetical in the first sentence, so it is not maximally concise.

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 zero-parameter tool with no output schema, the description adequately states the return format. However, it does not clarify how this tool relates to read_orientation or read_euler_angles, and it lacks details such as whether the quaternion is normalized or the coordinate conventions used. This leaves some ambiguity for an agent deciding among orientation-related siblings.

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, so parameter semantics are minimally relevant. The schema already covers this completely, and the description properly focuses on the return value instead of nonexistent inputs.

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 a specific action ('Read quaternion orientation data') and the exact resource/components returned (w, x, y, z). It distinguishes itself from siblings by specifying 'quaternion' rather than Euler angles, heading, or orientation in general, and adds clarifying context about gimbal lock.

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 provides no explicit guidance about when to use this tool versus alternatives such as read_euler_angles, read_orientation, or read_heading. The gimbal-lock statement implies a benefit of quaternions but does not tell the agent when to choose this tool over sibling tools.

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