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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false, so the safety profile is covered. The description adds a genuine behavioral fact beyond them: position is out of scope for this call. It does not discuss reversibility, required permissions, or what happens to fields not supplied, which keeps it short of 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?

Two sentences, zero filler. The action and its editable fields are front-loaded, and the position boundary plus alternative tool is placed last where a caller will check it before invoking.

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 token mutation with no output schema and annotations carrying the safety profile, the definition covers purpose, the ID lookup path, and the scope exclusion. It omits any mention of permissions or side effects on linked actors, a minor gap given the annotation coverage.

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 hidden/tokenId/rotation/actorLink/elevation are all documented in the schema, including edge notes like the 0-360 range and module version. The description mostly re-lists those same field names, adding only the ''visibility'' framing for the hidden flag. 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?

Names a specific verb (Update) and resource (token properties), then enumerates the exact editable fields: visibility, elevation, rotation, actorLink. It also draws a hard boundary against token-move for position, letting an agent distinguish it from the sibling without opening either schema.

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?

Provides the prerequisite ('Use token-list to find tokenId') and an explicit when-not with the correct alternative ('Position is NOT changed here — use token-move ... to relocate a token'). Both the lookup path and the routing decision are stated rather than implied.

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