render_preview

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

Annotations already declare readOnlyHint=true, and the description reinforces this with 'Never modifies the view'. It also adds useful behavioral context not in annotations: auto-stretch behavior by default, the stretch mode semantics, and the inline image plus file-path return. No contradiction exists.

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 information-dense, front-loading the core purpose before parameter details. The all-caps 'LOOK AT THE IMAGE.' is slightly noisy but does not seriously hurt clarity.

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?

Given a moderate parameter count and no output schema, the description covers the key behavioral contract and return format, but it leaves parameter semantics for id and max_edge to inference. It is usable, though not fully self-sufficient for an agent unfamiliar with the domain.

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 only 40%, but the description compensates partially by explaining the stretch enum values and default behavior. However, id and max_edge remain under-documented, and the description does not clarify how rect or linked behave beyond their schema descriptions. This is partial compensation, not complete.

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 states a specific action ('Renders a JPEG preview of a view'), the return format ('inline as an image plus its file path'), and explicitly notes it never modifies the view. This clearly distinguishes it from processing or cropping tools without needing to open the schema.

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 implies usage for visually inspecting a view, especially with auto-stretched linear data, but does not explicitly contrast it with sibling tools like crop_preview or compare_previews. There is no when-not-to-use guidance, leaving some routing to inference.

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