Past generations

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

With no annotations to rely on, the description transparently discloses the tool's output structure (prompt, rewritten prompt, references, stored image URL), ordering (newest first), and overarching purpose. It implies a read-only, non-destructive operation, which is behaviorally useful. However, it doesn't mention potential side effects (likely none) or clarify that it returns an empty list when no generations exist, leaving slight room for interpretation.

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 deliver complete value: the first lists all returned data and ordering, the second gives two concrete use cases. No unnecessary words or repetition. The description is front-loaded with the most critical info (what is listed) and remains highly scannable.

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?

For a tool with only two parameters and no output schema, the description is sufficiently complete. It explains what is returned, the ordering, and when to use it. Minor gaps exist: it doesn't mention pagination or default behavior of the 'limit' parameter, but the schema already covers the default value, so the description doesn't need to repeat that. Overall, a well-rounded description for the tool's simplicity.

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 covers 100% of parameters, and the description does not add parameter-specific details beyond what's in the schema. The phrase 'reuse a prompt' hints at how 'game' and 'limit' are used, but overall the description adds no new constraints or defaults. Per the rubric, a baseline of 3 is appropriate when schema coverage is high.

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 tool as listing all thumbnail generations for a game, with explicit scope ('for a game') and ordering ('newest first'). It goes beyond a generic label by enumerating the specific data fields returned (prompt, rewritten prompt, references, URL), which precisely distinguishes it from sibling tools like get_thumbnails that likely return thumbnail metadata.

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 description provides concrete use cases: 'find something made earlier and publish it with upload_generation, or to reuse a prompt that worked.' This tells the user when to select this tool, and even names a complementary tool. It stops short of explicitly contrasting with list_artist_channels or get_thumbnails, so it gets a 4 rather than a 5.

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