下载文件

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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the safety profile is covered. The description adds genuinely non-obvious behavior: the file lands in a random local staging directory (non-deterministic destination) and its size is verified against a known value, which an agent needs to know to locate and trust the result.

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?

A single compact sentence with no filler, front-loading the action, the target, the destination, and the post-condition. Every clause carries information.

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?

With an output schema present, return values need not be explained, and the two parameters are fully covered by the schema. The description supplies the missing operational context (staging destination and size verification); only error/failure handling is absent, which is a minor gap.

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 both parameters (server, remote_path) are already fully documented in the schema, establishing a baseline of 3. The description adds nothing about parameter semantics, and its mention of 已知大小 does not map to any schema field.

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 states a specific verb (下载) and resource (单个远程文件) plus the destination (本机随机 staging 目录) and a validation step (校验已知大小). The word 单个 implicitly contrasts with the sibling download_dir for directories, though it never names that sibling explicitly.

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?

There is no explicit guidance on when to use this tool versus read_text_preview, get_file_info, or download_dir, nor any stated prerequisites. Usage is only inferable from the description of what the tool does.

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