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

Annotations cover only the safety profile (readOnly, non-destructive, closed-world), and the description adds substantial behavior beyond that: holders are matched by CIK and SEC reporting links never by name, shares are restated onto today's split basis, change is versus the same holder's previous filing in the same source, % Out is of shares outstanding, and funds are never summed because their shares sit inside adviser 13F reports. These are non-obvious correctness rules an agent could not infer.

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?

Front-loaded with the core purpose and dense with substance; almost every clause carries a rule or a distinction. There is mild duplication with the schema on view/source definitions and the prose runs long as a single block, but it is not padded.

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 no output schema and six parameters over a complex ownership domain, the description still conveys the shape of the result (one row per holder, nested filings, restated shares, change basis, % Out), the view/source modes, and the routing to GetOwnershipSummary for totals. Nothing essential for correct invocation is missing.

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%, so the baseline is 3, but the description adds real semantics on top of the schema text — how the default view nests other filings and contained 13D/G, insider and fund disclosures, that view=all includes stale rows, and that view=ultimate lists each parent's members with the linking evidence. It does not add anything for offset/maxResults beyond the schema.

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?

States a specific verb and resource and enumerates exactly what 'holders' means (13F institutions, 13D/G filers, Forms 3/4/5 insiders, N-PORT funds), which is far more precise than the title alone. It only partially disambiguates from the crowded sibling set — GetOwnershipSummary is named, but GetTopHolders, GetHolderMix, GetBeneficialOwnership and GetFundsHoldingStock are not addressed.

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?

Gives clear context for use and one explicit alternative ('Use GetOwnershipSummary for the totals'), plus in-line guidance on which view/source to pick. It stops short of stating when-not-to-use this versus the other holder-oriented siblings.

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