Download by click

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

The description adds real context beyond the annotations by explaining that a click on the live page triggers the download and that this targets linkless buttons. It does not say whether the call waits for the download to finish, how failures or timeouts surface, or whether an existing file in destDir is overwritten — notable given idempotentHint=true on a write-to-disk operation.

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 sentence, front-loaded with the action, with the qualifying condition placed in parentheses where it belongs. No filler.

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 4-parameter, open-world interaction tool with no output schema, the description covers what it does and when, but leaves the agent guessing about completion semantics, return value (e.g., saved file path), and error/overwrite behavior.

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 all four parameters (nth, text, selector, destDir) are already documented in the schema. The description adds no meaning about how text vs. selector interact or how destDir is resolved, so baseline 3 applies.

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?

Specific verb+resource: it downloads a file, and the mechanism (clicking an element on the current page) is stated. The parenthetical 'download buttons without a direct link' implicitly separates it from the sibling `download`, though it never names that sibling.

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 parenthetical gives a clear triggering condition: use this for download buttons that lack a direct link. It does not explicitly name `download` or `click` as the alternatives to avoid, so the routing is inferred rather than stated.

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