Institution Style History

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

Annotations only declare readOnlyHint=true, so the description carries most of the load, and it delivers: it discloses that bands are measured against stated thresholds rather than the firm's own description, that active share is computed against every 13F filer's combined book, and that only closed quarters are scored (the newest quarter appears once its filing window closes). It omits return format and pagination details, keeping it from a 5.

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 purpose is front-loaded in the first clause and every sentence earns its place - the enumerated measurements justify their length because no output schema exists. The single sprawling second sentence with a long parenthetical is dense, but 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 only a readOnlyHint annotation, the description must describe the return payload itself, and it does by enumerating the bands and backing measurements (equity value, stock count, active share, top 10 weight, effective positions, turnover, holding period). The quarter-closure timing rule further completes the picture; only the ordering/pagination shape of the response is left implicit.

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 both parameters (maxPeriods, institutionName) are already fully documented in the schema, including the default, clamping range, and partial-CIK resolution behavior. The description adds no syntax or format detail beyond what the schema provides, so baseline 3 applies.

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 states a specific verb+resource ('Get an institutional 13F filer's portfolio style quarter by quarter') and enumerates the exact style/turnover/horizon bands and underlying measurements, which sharply distinguishes it from sibling tools like GetInstitutionPortfolio or GetInstitutionSummary. It stops short of explicitly naming a sibling it differs from, so it is clear but not fully differentiated.

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?

Usage is implied by the purpose - an agent would infer this is for time-series style analysis of a single filer - but there is no explicit when-to-use, when-not, or named alternative among the many institution siblings (GetInstitutionPortfolio, GetInstitutionQuarterlyActivity, CompareInstitutionPortfolios). The 'Closed quarters only' note is a data-availability caveat rather than routing guidance.

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