Create a hosted chart

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

With no annotations, the description carries the transparency burden. It discloses key behavior: returns a permanent, hosted URL that renders server-side and works without a client-side library. However, it omits operational details like authentication (icac), network effects, rate limits, or the fact that format=png fetches the image, which are important for a creation tool.

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 two concise sentences that front-load the action and result. It includes valuable context (permanent URL, server-side rendering, no client-side library) without waste. Every word adds meaning.

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 the tool's complexity (12 parameters, nested objects, no output schema, no annotations), the description gives a high-level purpose but does not mention the required 'type' parameter, the optional output format (url/png/both), or how to handle authentication. The rich schema compensates, but the description alone is not fully complete for correct invocation.

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 the baseline is 3. The description itself adds no parameter-level meaning, but the schema fully documents each parameter, including nested objects and constraints, so the agent can rely on the schema.

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 tool creates a hosted chart URL from a semantic chart description, listing supported chart types. It names the specific resource and outcome (Image-Charts URL), but does not explicitly differentiate itself from siblings like image_charts_url.

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 use for server-side rendering and embedding without a client-side library, providing some context. However, it does not explicitly state when to use this tool over alternatives like image_charts_url or list_chart_types, nor does it mention exclusions.

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