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

Beyond the readOnly/idempotent annotations, the description discloses that data is read from public filings and 'may contain errors', and it instructs the agent to 'always show the source link' and not present results as personal investment advice. This is important behavioral context the annotations do not provide.

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 main description is two sentences with the core action front-loaded, followed by essential caveats. Every sentence adds value and there is no redundant or filler text.

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 a single parameter and no output schema, the description covers what the result contains (holding mix, country, largest positions, as-of dates, source links), the data source, and accuracy limitations. An agent has enough context to invoke it correctly and handle its output appropriately.

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% and the ticker parameter already has a useful description with an example and a search_funds fallback. The tool description does not add new parameter detail beyond framing the data as closed-end fund holdings, so the baseline of 3 is appropriate.

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 opens with a specific verb and resource: it 'Describes what a closed-end fund holds' and enumerates the exact dimensions (mix by type/country, largest positions) plus provenance from SEC filings. This clearly differentiates it from sibling tools like get_fund or get_fund_events, even without naming them.

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 intended use is implied by the description, but there is no explicit guidance about when to prefer this over sibling tools such as get_fund, get_fund_events, or which_funds_hold. The only alternative it names is search_funds, and that is in the schema's parameter description rather than the tool description.

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