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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds that the tool returns 'latest filing and its investors,' which is useful context, but it does not disclose any additional behavior such as pagination, rate limits, or relationship to other resources.

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, short phrase with no filler or redundant information. Every word contributes to specifying what the tool returns, making it highly concise and well-structured.

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 simple single-parameter retrieval tool with an output schema and strong annotations, the description is largely sufficient. It clearly states the core return data, but it could be slightly more complete by explaining what constitutes 'latest filing' or what investor details are included, though the output schema likely covers these.

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%: the single parameter 'slug' is fully described with examples and a clear definition. The description adds no extra parameter meaning beyond what the schema already provides, so a baseline score 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 'One fund's latest filing and its investors' clearly identifies the resource and what data is returned, distinguishing it from sibling tools like fund_history and fund_holdings. However, it lacks a explicit verb (e.g., 'retrieves'), relying on the title and name for the action.

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 no guidance on when to use this tool versus alternatives. Sibling tools such as fund_history and fund_holdings likely overlap in functionality, but no comparison or exclusions are mentioned. The only implied usage is that this tool focuses on a single fund's latest filing and investors.

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