Render ECharts

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

With no annotations, the description carries the full burden. It discloses that rendering happens server-side without a browser, returns raw SVG plus the echoed option, and that canvas/PNG raster rendering is not yet available (v1.1). This is valuable behavioral context, though it does not mention what happens when canvas/dual is requested or other edge cases like error handling.

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 very concise: two sentences that efficiently state the action, output format, return value, and version limitation. Every sentence earns its place with no redundancy or fluff.

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?

Despite being brief, the description covers essential context: server-side rendering, SVG output, return payload, and the upcoming canvas/PNG support. Given the rich input schema and presence of an output schema, the description fills the main gaps. It misses explicit usage guidance relative to siblings and error handling for unsupported renderer modes, but is otherwise sufficiently complete for a complex tool.

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 input schema covers 100% of parameters with descriptions, so the baseline is 3. The description adds no new parameter details beyond mentioning the 'echoed option', which overlaps with the schema's description of the 'option' parameter. Thus, it does not meaningfully enhance parameter understanding.

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 defines the tool's purpose: 'Renders an Apache ECharts visualization to SVG' with the specific verb 'renders' and explicit output format. It also adds scope context ('server-side, no browser') and distinguishes from siblings by focusing on rendering rather than validation or listing.

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 provides contextual usage ('server-side, no browser') and notes that canvas/PNG is not yet available, which implies when to use it (when SVG is needed). However, it gives no explicit guidance on when to choose this over sibling tools like validate_echart_option or list_chart_types, and lacks any exclusions or alternative recommendations.

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