download

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

With no annotations, the description carries the full burden and does disclose meaningful traits: that it is a fallback path, that Chrome settings/policy may trigger a save dialog, and that permission should be obtained before background use. It stops short of stating auth requirements, rate limits, or the return value, so not a 5.

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 of reasonable length, but the broken punctuation ('via:"page"', stray quotes) reads as garbled and hurts front-loading. The fallback rationale leads, which is good, but execution is sloppy.

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-param download tool with no output schema, the description covers the primary use context and a key risk (save dialog). It omits what success/failure returns, the timeout default behavior, and how savePath relocation interacts with the fallback, leaving gaps an agent would need.

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 75% and the schema already documents spaceId, timeout, and savePath. The description adds no syntax or format detail for these, and its 'via page' reference does not correspond to any declared parameter, which is more noise than signal. Baseline 3 is appropriate.

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?

States a specific verb+resource (download a URL) and distinguishes itself from the fetch sibling by naming the exact condition (fallback when fetch with binary:true and savePath fails). The mangled 'Try via:"page"' fragment introduces a mode that doesn't map to any schema parameter, adding minor confusion to an otherwise clear purpose.

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?

Explicitly frames this as a fallback and names the alternative (fetch with binary:true/savePath). It also gives the 'page' condition for sites needing credentials/Referer and instructs obtaining permission before background use. No explicit when-not-to-use beyond the fetch comparison, so not quite a 5.

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