Export a PNG of the board

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

The readOnlyHint annotation already establishes the operation is non-mutating. The description adds the practical purpose (visual self-check) but doesn't disclose other behavioral details like output format, size limits, or performance implications. Since annotations cover safety, a 3 is appropriate.

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, front-loaded with purpose and usage guidance. No filler or redundant repetition of schema information. Every sentence earns its place.

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 simple read-only rendering tool with no output schema and all-optional params, the description covers the essential use case and outcome. It doesn't specify return format (e.g., URL vs binary), but 'return it as an image' is sufficient given the tool's simplicity and optional params.

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% with clear descriptions for all three parameters (scale, nodeIds, maxDimension). The description adds a small amount of context by mentioning page/selection/nodes, which maps to nodeIds, but doesn't significantly augment the schema's already thorough parameter documentation. Baseline 3 is warranted.

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 states the function: 'Render the page, a selection, or specific nodes to a PNG and return it as an image.' It names the exact resource (page/selection/nodes) and output (PNG image), distinguishing it from sibling tools like create_diagram or list_nodes.

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?

Provides explicit usage context: 'This is how you visually check your own work — look at the result and fix layout problems before telling the user you are done.' It implies when to use (before finishing a task) but doesn't list alternatives or when not to use it, so it falls short of a 5.

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