get_13f_holdings

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

Annotations already cover read-only, idempotent, and open-world semantics, so the bar is lower. The description still adds value by disclosing that it returns the *latest* report period and by explaining the two different row granularities (issuer-level vs security-level).

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 summary sentence followed by compact Args/Returns sections; every line carries information. Slightly verbose in the Returns block, but the top_issuers vs top_positions distinction earns its space.

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?

An output schema exists, so return-value explanation is not strictly required, yet the description clarifies the two result groupings an agent must choose between. Coverage of a two-parameter tool is otherwise complete.

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 0%, so the description must carry the load, and it does: ticker_or_cik is explained as manager ticker or CIK with concrete examples ('BRK-B', '1350694'), and limit is clarified as 'number of top positions to return' with a default of 25.

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+resource: 'Get the latest 13F portfolio of an institutional investment manager.' That is concrete enough to separate it from nearby tools such as get_beneficial_ownership and get_insider_transactions, though no sibling is named explicitly.

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 resource ('13F portfolio'), and the Returns text hints at selection ('use this for largest holdings'). But there is no explicit when-to-use/when-not guidance or comparison to alternative holdings-related tools.

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