affinity_render_selection

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds the output format (JPEG), which is useful, but with no output schema it never says how the image is delivered (base64 payload, file path, or attachment) or what happens when nothing is selected.

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?

One short, front-loaded sentence with no wasted wording. Its brevity is appropriate in form, though it leaves substantive gaps that the other dimensions penalize.

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 and no annotation of return behavior, the description should explain what the render returns and what 'selected nodes' means (current user selection in the open session). Neither is addressed, leaving a render tool's result contract undefined.

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 single parameter document_session_uuid has 0% schema description coverage and the description never mentions it. It does not clarify that the UUID identifies the document session whose selection is rendered, so the description adds no meaning beyond the parameter's name.

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 uses a specific verb plus resource ('Render the selected nodes ... as a JPEG'), which tells an agent exactly what the tool produces. It does not explicitly distinguish itself from the sibling affinity_render_spread, which renders a whole spread rather than a selection, so the boundary is left implicit.

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?

There is no when-to-use guidance, no mention of prerequisites, and no pointing at affinity_render_spread or affinity_export as the alternatives for whole-spread or file export. The agent must infer the choice from the tool name alone.

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