Institution Sector Allocation

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

With only readOnlyHint=true in annotations, the description carries real behavioral weight: it discloses the markdown table return, descending % sort, the collapsed 'Unclassified' row, data provenance (report-date closing prices with fallback to filer values, possibly zero), and the ambiguity handling for partial names. This is far more than the annotations 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?

Three dense sentences with the core purpose and grouping default front-loaded; the caveats about pricing fallback and ambiguous names are placed after the essential facts. Slightly heavy for the tool's simplicity, but no sentence is filler.

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?

No output schema exists, so the description properly explains the return format, ordering, and the Unclassified bucket, and it covers the default/fallback behavior for both optional parameters. Nothing an agent needs to invoke this correctly 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 meaning beyond the schema: it clarifies that groupBy toggles fine-grained industry versus broad sector rollup and that a non-resolving name yields candidates 'instead of selecting silently.' The reportDate snapping rule largely duplicates the schema text.

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 ('Get an institution's 13F portfolio allocation') plus the grouping axis and output shape, which separates it from sibling allocation tools like GetInstitutionPortfolio, GetHolderMix, and GetTopHolders. An agent can tell what it returns (industry- or sector-level allocation table) without opening the schema.

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: use it per report quarter with a latest-date default, and route to SearchInstitutions when an exact CIK is needed. It also warns that ambiguous partial names return candidates rather than silently selecting. It stops short of explicitly naming a sibling to use instead for related portfolio views.

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