briefing_stock_watchlist_custom_sources

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

No annotations are provided, so the description must carry the full burden. It discloses the three modes (add, remove, view) and the placeholder replacement behavior, but does not mention potential side effects (e.g., persistence), required permissions, or whether actions are reversible. This is adequate but lacks depth for a mutation tool.

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 compact, well-organized paragraph. It front-loads the core purpose, then explains parameter behavior and placeholder support without any redundant filler. Every sentence contributes useful 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?

For a tool with 4 parameters, 1 required, and no output schema, the description covers the main use cases and parameter interactions. It lacks an explicit note about the return value or output format, but for a simple management tool, the provided context is sufficient. Sibling tools are not referenced, but the trigger phrases help disambiguate.

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%, giving a baseline of 3. The description adds value by explaining the semantics of omitting both add_urls and remove_urls (view mode) and the placeholder substitution for {ticker} and {company}, which is not obvious from the schema alone.

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 tool manages custom RSS sources for a specific stock, with a specific verb ('管理') and resource ('某只股票的自定义信源'). It distinguishes itself from sibling tools by focusing on per-stock custom sources and provides concrete example user utterances that trigger it.

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 explicitly states when to call the tool with example user phrasings, and explains that omitting add_urls and remove_urls results in viewing the current list. However, it does not mention when not to use it or contrast with alternative tools like briefing_add_sources or briefing_get_sources, which slightly reduces clarity.

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