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

With no annotations, the description carries the full burden. It discloses that the tool returns URLs (and that you must fetch files yourself), and explains the asset formats in detail. It doesn't mention error behavior, rate limits, or authentication, but for a simple retrieval tool this is acceptable. It does not claim any mutation or side effects.

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 sentences with no filler. The first sentence states the purpose and asset types; the second gives the return type and an actionable instruction. Front-loaded with the key information, and every word earns its place.

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?

The description covers the core functionality: what it returns (URLs) and how to use it (fetch with own tools). It explains asset types. However, with no output schema, it doesn't describe the structure of the returned URLs (e.g., object vs array, temporary expiry) and doesn't explicitly state the prerequisite of having a valid generation_id from a prior generation. For a simple tool this is adequate but not comprehensive.

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%, so the baseline is 3. The schema descriptions are sparse: 'generation_id' just says 'Generation id' and 'variant' gives range and default. The tool description adds context by tying generation_id to a generated asset, but doesn't elaborate further. It doesn't add syntax or format details beyond the schema.

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 states the verb 'Get' and the resource 'download URLs for a generated asset', and explicitly names the two formats (GLB and Roblox Studio zip) with details about their use. It distinguishes itself from siblings like generate_asset and generate_variants by focusing on retrieval rather than creation.

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 implies the use case: after a generation, fetch the download URLs, then use your own file tools to actually download. It gives an explicit instruction about fetching. However, it doesn't explicitly state when not to use it or contrast with siblings, though the distinction is obvious given the tool name and sibling context.

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