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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds value beyond that: 'Read-only and free of charge' plus the cross-tool contract that the returned id feeds the generation tool's style parameter. Doesn't note pagination/limit behavior, but the key behavioral facts are present.

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, zero filler. The primary purpose is front-loaded and the agent-relevant contract (id usage) is placed at the end where it's most action-guiding.

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?

A read-only discovery tool with full schema coverage and no output schema. The description covers purpose, filters, safety, cost, and the downstream id contract, so an agent has everything needed to call it and use 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?

Schema coverage is 100% and enums are documented, so the schema carries the parameter load. The description still adds framing by naming the exact filter dimensions and the valid language values, reinforcing what to filter on. Baseline 3 is exceeded by this reinforcement.

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 (Lists) and resource (Studio99 calligraphy font styles) with the exact attributes returned (languages, moods, use cases). Clearly distinguishes itself from the write siblings create_studio99_project and generate_calligraphy by being the discovery/listing operation.

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?

Explains filtering conditions ('optionally filtered by language, mood or use case') and routes the agent to the generation tool by noting the id is what 'the generation tool accepts as its optional style value.' Lacks an explicit 'call this before generate_calligraphy' statement, but the relationship is clear.

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