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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, and the description adds genuinely new behavioral context: HP is read from the token rather than the master Actor, which matters for unlinked tokens after damage. The unlinked_character_token warning and its prescribed remediation (module 8.14+) is exactly the kind of non-obvious operational detail structured fields cannot convey.

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?

Front-loads the core purpose and return fields, then layers caveats; every sentence carries information. Slightly awkward phrasing in the warning clause ('warning unlinked_character_token = ...') costs a point for readability but not for waste.

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?

With no output schema, the description takes on the burden of describing returns and does so by listing the emitted fields and the token IDs used by sibling tools. Combined with the unlinked-token caveat, an agent has everything needed to call it correctly and interpret the result.

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?

There is a single parameter with 100% schema description coverage; the schema already says 'Scene ID (omit for active scene)'. The description's 'Omit sceneId for the active scene' repeats that fact rather than adding format, default-resolution, or multi-scene semantics, so 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 and resource ('List all tokens on a scene') and enumerates the fields returned (positions, HP, AC, conditions, disposition, actorLink). It also distinguishes itself from the sibling mutators by naming token-move, token-update and token-delete as downstream consumers of the IDs it returns.

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?

Gives a concrete conditional ('Omit sceneId for the active scene') and a routing rule for the unlinked_character_token warning ('fix it with token-update actorLink true, not by editing the actor'), which steers the agent away from a wrong alternative. It stops short of an explicit when-not-to-use statement, so it is strong but not exhaustive.

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