Preview image

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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds a genuinely useful behavioral caveat beyond the annotations: the image reflects the app's last save, not the user's latest edits, which sets correct expectations about staleness.

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 core facts are front-loaded, but the draft is redundant: 'a quick look without opening the app' is restated as 'a quick look ... with no app', and the last-save caveat is stated twice. Tightening to two sentences would lose nothing.

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?

An output schema exists, so return-value explanation is unnecessary. The description covers the key behavioral nuance (stored vs current render) and the sibling alternative, leaving no decisions an agent must make unaddressed.

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 both parameters (path, out_dir) are already documented in the schema. The description adds no extra semantics about path formats or the temp-folder default, so the baseline of 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 (Extract) and resource (the stored preview image / first page/slide), the output format (JPEG) and the return (its path). It clearly distinguishes itself from the sibling keynote_slide_image by contrasting a stored preview with a live render.

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 states when to use it ('for a quick look at the stored first-page preview with no app') and names the alternative plus the condition that selects it ('to see a slide as it renders now, use keynote_slide_image'). The routing decision is fully spelled out.

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