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

With no annotations provided, the description carries the full burden and does it well: it discloses auth (no API key), cost (free), result ordering (newest first), and the semantic meaning of the 'default' marker. Only pagination behavior is left unstated, 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?

Two dense sentences with the core purpose front-loaded and no filler. The parenthetical inventory of per-category detail fields is long but earns its place by previewing the return shape in the absence of an output schema.

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?

Without an output schema or annotations, the description supplies the essentials: what is returned (id, price, capability/voice/resolution details), ordering, filterability, the default-model rule, and cross-tool linkage. Nothing needed to call it correctly is missing.

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 four parameters (limit, search, category, capability) are already documented in the schema. The description restates filtering by category and search but adds no syntax, defaults or edge-case detail beyond what the schema provides, 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 the AI models GenMagic runs') plus ordering ('newest first') and the fields returned. It is unmistakably distinct from the generate_* siblings, which it references by name.

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?

Explicitly routes the agent: 'Pass a model's id as model to generate_text, generate_image...' and explains that the model marked default runs when none is named, including the generate_text/no-type case. This is exactly the when-to-use context an agent needs before invoking a generation tool.

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