List figures

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

The readOnlyHint and idempotentHint annotations already establish the safety profile. The description adds useful behavioral context: it returns figure attributes plus stored keyframes, and frame selection depends on either the supplied frame number or the playhead. It does not discuss pagination behavior for the limit parameter, which is a minor omission.

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?

Three sentences, each carrying distinct information: what is listed, how frame selection works, and how to use the returned ids. It is front-loaded with the core purpose and contains no filler.

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 read-only listing tool with full schema coverage and annotations, the description is nearly complete: it names the returned figure fields and keyframes, explains frame behavior, and directs reuse of ids. It could mention the default limit or pagination behavior, but that is already present in the schema and not essential.

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 all five parameters are already documented in the schema. The description adds some meaning around frame selection (keyframe number versus playhead) but does not add detail for name, layer, limit, or project beyond what the schema provides. 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?

The description gives a specific verb and resource: 'List the figure instances the animation shows,' and enumerates the returned fields (ids, names, layers, position, scale, opacity, colour, keyframes). This is enough for an agent to distinguish it from figure_describe or layer_list without opening the 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?

It clearly explains the key usage condition: supply a keyframe number to list figures at that moment, otherwise the playhead determines the frame. It also says to reuse returned ids with other figure and pose tools. It does not explicitly state when to prefer figure_describe over figure_list, but the listing use case is clear.

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