set_camera_rig_rail_position

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

Annotations already declare the safety profile (not read-only, idempotent, destructive, closed-world), so the description carries a lighter burden. It usefully adds the return shape ({rig_actor_name, position, success}), which is valuable since no output schema exists, but it says nothing about what the 'destructive' hint means here or any permission requirements.

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 tight sentences, front-loaded with the core action and the range semantics, followed by the return shape. Every clause carries information; no filler or repetition.

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 simple two-parameter setter, the description covers the action, the parameter semantics, and return values (needed since no output schema exists), and the annotations cover safety. Only the absence of usage/prerequisite guidance keeps it from being fully complete.

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 100%, so both parameters are already documented in the schema, including the 0.0–1.0 range that the description restates. The description adds no syntax or behavior beyond what the structured data already provides, so the baseline 3 applies.

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 ('Set') plus the exact resource ('camera position along a CameraRig_Rail') and defines the parameter's meaning (0.0 = start, 1.0 = end). An agent can distinguish this from sibling setters like set_camera_transform or set_camera_rig_root_node, though the description never explicitly names an alternative.

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?

No when-to-use or when-not-to-use guidance is present. With siblings such as set_camera_transform, set_camera_rig_root_node, and set_camera_node_parameters in the same family, the agent gets no signal about which rail-position tool to pick or any prerequisites (e.g. that a CameraRig_Rail actor must already exist).

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