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

No annotations are provided, so the description carries the full behavioral burden, yet it only states the input form. It does not disclose that this is a read-only fetch, what the response contains, whether auth is mandatory, or any rate limits, leaving most behavioral traits unstated.

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 the key input requirement front-loaded in the parenthetical. Nothing is wasted, though the extreme brevity limits how much it can convey.

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 simple 3-parameter, no-output-schema detail fetch, the description plus fully covered schema is largely adequate. However, with no annotations and no mention of return content or auth expectations, it is only minimally 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 coverage is 100%, so the baseline is 3, but the description adds real value by specifying the exact share_url format with a concrete example (https://weixin.qq.com/sph/xxxx), which the schema's terse '分享链接' does not provide.

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 resource and action: retrieving details for a WeChat Channels (视频号) video work. This distinguishes it from platform siblings such as bili_video, douyin_video, and yt_video by naming the platform, though it does not explicitly call them out as alternatives.

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?

Usage is only implied: the parenthetical tells the agent a share_url is required, which hints at when the tool applies. There is no explicit when-to-use/when-not guidance and no named alternative among the many sibling video tools.

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