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

With readOnlyHint already flagging a safe read operation, the description adds useful behavioral context: 'FREE' signals cost behavior, and it discloses mode-dependent response content (index vs full frame lists). It does not mention rate limits or auth, but for a read-only menu tool with this annotation, the additional context is sufficient.

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 dense but economical; every sentence adds either domain context or call behavior. The leading 'FREE' and core purpose are front-loaded, and the rest of the content explains invocation modes without filler. The first sentence is a long enumeration, but it remains readable and purposeful.

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?

Given no output schema, the description carries the burden of explaining return values, and it does: no arguments yields the index, while family+type yields full frame lists. It also mentions frame counts per detail level and resolution ceilings, which are the key data points an agent would need. It is complete enough for a read-only menu tool.

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 schema already documents both parameters, so the baseline is 3. The description goes beyond by explaining the no-argument case, the family+type combination, and the relationship to generate_sheet. This adds practical meaning to the parameters rather than just repeating schema names.

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 identifies the resource as the menus/options a sheet is made from: kinds, keyable grounds, art styles, animation sequences, levels, and image models. It also differentiates from generate_sheet by stating 'The ids go straight into generate_sheet.' It lacks an explicit verb like 'returns' or 'lists,' but the behavioral intent is unambiguous from 'No arguments = the index, ids and one-liners.'

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 explicitly specifies two calling modes: no arguments returns the index, and family + type returns that type's sequences with full frame lists. This tells the agent exactly when to call with parameters versus empty. It names generate_sheet as the downstream consumer but does not explicitly discuss when not to use this tool versus alternatives.

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