Download Visual

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

Annotations already declare readOnly, idempotent and non-destructive behavior. The description adds real value by clarifying that only a URL is returned (not the binary) and that the visual remains stored in the workspace — i.e., nothing is moved or deleted. It stops short of covering URL lifetime or auth requirements.

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 short sentences, front-loaded with the core action, then the return value, then storage semantics. Little waste, though the third sentence is slightly tangential.

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?

With no output schema, the description correctly tells the agent the return is a direct image URL, which is the key missing piece. However, for a two-parameter tool with 0% parameter documentation, the meaning of output_index and any URL expiry behavior are left unexplained.

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 0% and the description does not compensate: 'a specific output' hints at output_index but never states that it is a zero-based index defaulting to 0, and nothing explains the expected generation_id format.

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: get the download URL for a specific output of a completed generation. This is distinguishable from get_generation (metadata) and export_visuals (bulk export), though the differentiation is implied rather than stated explicitly.

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?

The phrase 'from a completed generation' implies a prerequisite, but the description never names alternatives such as get_generation or export_visuals, nor says when to prefer one over the other. Usage is inferable rather than guided.

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