Get a slide thumbnail

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

The description adds substantial behavioral detail beyond the annotations: the two output modes (contentUrl vs local file), the short-lived URL (~30 minutes), the restriction to Google's image hosts, size options with pixel dimensions, and the quota cost. This is exactly the kind of context an agent needs to predict runtime behavior.

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?

The description is compact and front-loaded: the first sentence states the core purpose, followed by behavior, size, and usage context. Every sentence earns its place with dense, useful information and no filler or repetition.

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?

There is no output schema, so the description correctly explains return behavior ('returns contentUrl + width/height') and the local-file alternative. It also covers URL expiry, download restrictions, size defaults, and quota impact, giving an agent everything needed to call it correctly.

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 description adds meaningful semantic value by stating the default size ('large (1600px, default)') and clarifying the behavior of output_path (omitted = returns contentUrl; provided = downloads to local file), which goes beyond the schema's individual parameter descriptions.

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 names a specific verb ('Renders') and a clear resource ('one page (slide, layout or master) as a PNG'), and immediately differentiates this tool from JSON-based alternatives by stating 'the JSON never shows rendering.' This makes the tool's purpose unambiguous.

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 clearly states when to use the tool: 'This is the way to SEE what a slide actually looks like — the JSON never shows rendering.' It also warns that it 'Counts as an expensive read in the API quota,' implying it should be used judiciously. However, it does not explicitly name sibling tools like get_page, so the routing is slightly less direct than a full 5.

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