pm_etf_holdingsTrack global gold and silver ETF holdings changes to gauge institutional fund flows and asset allocation trends.
获取全球黄金或白银ETF持仓量变化数据，用于判断机构资金流向
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | 返回数量(int)，建议30-90 | |
| metal | No | 金属类型，支持: gold(黄金), silver(白银) | gold |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states that the tool fetches ETF holdings-change data; it does not describe return format, units, update frequency, sorting, pagination, or other behavioral traits.
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 sentence with no filler words, and it front-loads the verb and resource before the purpose. It is efficient and easy to parse, though it lacks any additional structure such as examples or usage notes.
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, has only two fully documented parameters, and no output schema, but the description does not explain what the returned data looks like, what units or time periods are involved, or how this tool differs from sibling precious-metal data tools. It is minimally sufficient but leaves gaps for an agent that needs to interpret the results.
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 the baseline is 3: both parameters already have meaningful descriptions, including allowed values for 'metal' and a suggested range for 'limit'. The description does not add significant meaning beyond this, though it reinforces the gold/silver focus.
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 uses a clear verb ('获取') and a specific resource ('全球黄金或白银ETF持仓量变化数据'), and adds a purpose ('用于判断机构资金流向'). It is distinct enough from generic fund or stock tools, though it does not explicitly contrast with sibling precious-metal tools.
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 stated purpose implies when to use it (when analyzing institutional precious-metal ETF flows), but there is no explicit guidance on when not to use it or which sibling tool to choose instead. Alternatives like pm_spot_prices or pm_comex_inventory are not mentioned.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.