fetch_wechat_article

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

Annotations only declare openWorldHint and destructiveHint=false, so the description carries most of the burden and delivers: it discloses write side effects (saving HTML and TXT files), the exact returned payload, the access limitations (no auth bypass, paid content blocked), and an untrusted-content prompt-injection warning. That last point is behaviorally important context beyond any structured field.

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 tight sentences: purpose and outputs first, then URL eligibility, then the injection warning. Every sentence carries distinct, decision-relevant information with 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?

With no output schema, the description correctly specifies the return values (title, account name, text) and the file artifacts produced. Parameters are fully documented in the schema and the security/limitation context is supplied, so an agent has everything needed to call this safely.

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 baseline is 3, but the description adds real semantic constraints the schema lacks — the https/mp.weixin.qq.com/s domain restriction and public-access requirement for url. It says less about save_dir than the schema does, but the schema already covers that fully.

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 and resource (读取微信公众号文章) and enumerates exactly what comes back: title, account name, and full plain-text body, plus the HTML/TXT side effect. There are no sibling tools, so no disambiguation is needed and none is missing.

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?

It gives concrete eligibility constraints an agent can check before calling: only publicly accessible HTTPS mp.weixin.qq.com/s links, and it explicitly rules out bypassing login, payment, or WeChat environment verification. There are no alternative tools to route against, so this is close to complete, though it doesn't say what to do when a link fails those checks.

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