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

Beyond destructiveHint=true and openWorldHint=true, the description explains exactly what is exposed: public anonymous access, a live view that reflects later changes, interactivity (rotate, measure, section, download, edit a copy), and the important privacy detail that the drawing's script is not included. It also states the one-link-per-drawing invariant and that repeat calls return the same link, which is behavioral context the annotations cannot express.

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 core promise is front-loaded in the opening clause and there is no filler; every clause (capabilities, script exclusion, usage trigger, single-link rule) adds information. The downside is that the main sentence is very long and semicolon-chained, which makes it harder to scan than a short bulleted structure would be.

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 two-parameter tool with full schema coverage and no output schema, the description covers access model, recipient capabilities, data exposure, and link lifecycle thoroughly. The only soft spot is that it never plainly states what the call returns (presumably the URL), leaving that to be inferred from "share gives the same one".

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% and the action enum already documents on/renew/off, so the parameters are largely self-explanatory. The description only indirectly adds meaning by noting that each drawing has exactly one link and that a repeat request yields the same one, which clarifies the 'on' action's effect but does not address the drawing parameter at all. Baseline 3 is appropriate when the schema carries the parameter detail.

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 names a concrete verb and resource: it produces a public link to a drawing that anyone can open without a uCAD account. It also contrasts this with the drawing's own pre-existing link (?d=), which only works for the signed-in user, so an agent can separate 'share' from 'drawings'/'view' without opening another 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?

"Use it when the user wants to show or send the model to someone else, or post it" gives an explicit trigger, and the same sentence explains why the ordinary ?d= link will not do. The action enum in the schema then covers the renew/off routes, so the description handles the when-to-use question rather than leaving it to inference.

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