Downloads

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

With readOnlyHint=true already covering the safety profile, the description adds real behavioral detail: the wait action blocks until completion, and read converts text files to text, PDFs to extracted text, and everything else to path/type/size. It doesn't say what wait actually returns or what happens when a download never finishes.

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 purpose sentence followed by a tightly packed per-action breakdown, front-loaded so the agent learns what the tool is before the action details. 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 3-param tool with no output schema, the description covers purpose, action semantics, and the read return format well enough to invoke correctly. It stops short of describing list/wait return shapes or timeout/failure behavior, which an agent relying on no output schema would benefit from.

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 coverage is only 33%, so the description must carry the load for action and id — and it does, defining all three enum values and explaining that id is optional for read with a newest-wins default. timeoutMs is left to the schema, which documents it.

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 first sentence names a specific verb+resource (downloaded files) and the rest enumerates the three actions, so an agent can tell this apart from siblings like browser_upload, browser_read, and browser_wait without opening any schema. Each action's role is stated in a distinct clause.

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?

"wait" is tied to a concrete trigger ("the one just started (by a click)") and "read" is scoped to finished downloads, which gives clear selection context. What's missing is explicit routing away from siblings (browser_upload, browser_network, browser_read) or any statement of when not to use this tool.

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