briefing_get_sources

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

No annotations are provided, so the description carries the behavioral disclosure burden. It implicitly indicates a read-only operation with '查看' (view), which is useful, but it lacks details on return format, pagination, or behavior when there are no sources. Given the tool's simplicity, this is minimally adequate.

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?

The description is a single, concise sentence that front-loads the main purpose and trigger examples. It contains no filler or redundant information, making it highly efficient.

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?

The tool is simple with one optional parameter and no output schema. The description implies the tool returns the list of subscribed sources ('查看...哪些新闻来源') but does not explicitly describe the output structure or how the token parameter affects the result. This minor gap prevents a perfect score, but overall the description is sufficient for an agent to use the tool correctly.

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?

The only parameter (token) has a complete description in the schema, so the schema covers 100% of parameter semantics. The description adds no additional parameter information, hence the baseline score of 3.

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 clearly states the action (查看/view) and the resource (当前订阅的新闻来源/currently subscribed news sources), and includes example user queries that trigger this tool. This distinguishes it from sibling tools like briefing_set_sources and briefing_add_sources, which modify subscriptions.

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?

The description provides explicit trigger phrases ('我现在订阅了什么', '看看我的信源') indicating when to call this tool. However, it does not explicitly mention when not to use it or name alternative tools, so it stops short of a 5.

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