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

The annotations already declare destructiveHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful behavioral context the annotations cannot convey: the credit cost per started minute of session, the fact that the session expires 3 minutes after the last call, the 10-file/20 MB limits, and the return value (URL and title).

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?

Three sentences, each carrying distinct information (target, file format and limits, cost and session lifetime), with no filler. The target and the file-format rules are front-loaded. It is dense but every clause does work.

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?

Because there is no output schema, the description carries the burden of describing the return value, and it does say it returns URL and title. It also covers limits, cost, and session expiry. What is missing is failure behavior and whether the element must be a file input, but for a two-parameter tool this is nearly complete.

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 then adds real meaning on top: it spells out the two accepted file shapes ({'url': ...} versus {'file_id': ...} for a file uploaded to Cotlet first) and clarifies that 'element' is the number in the element list of the current page, which is more concrete than the schema's wording.

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 specific verb ('purpose: puts files into') and a precise target: the file field of the current page, or the file picker opened by an upload button, addressed by element number. That is far more specific than the title alone. It stops short of differentiating itself from the sibling cotlet_upload_file, which an agent could easily confuse with this browser-scoped tool.

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 usage is implied rather than stated: the agent learns this applies to the 'current page in the user's PeoplePerHour Cloud Browser' and to file pickers opened by upload buttons. However, there is no explicit guidance on when to use this versus cotlet_upload_file, nor any prerequisites (for example, that a browser session must already be open).

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