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

Since no annotations are provided, the description bears full responsibility for behavioral disclosure. It mentions the 45-day reporting lag, long-only nature, cost ($0.02), and that it is not investment advice. This fully informs an agent about the tool's characteristics without contradicting any annotations.

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 concise (three sentences) and front-loaded with the most important information: what the tool returns (number of holders, aggregate shares/value, QoQ change). It then adds relevant context (lag, asset class, cost) without unnecessary elaboration. Every sentence earns its place.

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?

Given the tool has an output schema (not shown), the description adequately overviews the return values. It mentions key context: lag, long-only, cost. However, it lacks explicit mention that the snapshot is for the most recent available quarter and does not specify that the cik parameter is required. This leaves minor gaps in completeness.

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 input schema has 0% description coverage; the only parameter 'cik' is not described. The tool description does not mention the parameter or its role (e.g., the CIK number identifying the company). While the name 'cik' is standard, the description fails to add meaning beyond the bare schema, which is insufficient given the low schema coverage.

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 it is a '13F institutional ownership snapshot' with specific data points: number of holders, aggregate shares/value, and quarter-over-quarter change. This distinguishes it from sibling tools like insider_activity or short_pressure, which cover different financial data.

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 implies usage for institutional ownership data with a 45-day reporting lag and long-only focus, helping an agent decide whether this tool is appropriate for a given query. However, it does not explicitly state when to use this tool versus alternatives like company_facts or industry_aggregate, which might also provide ownership-related information.

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