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

Annotations already carry the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=false), lowering the disclosure burden. The description adds useful context by scoping the data to 'tracked funds' and previewing the returned content, but it does not clarify semantics like how 'last-quarter moves' are computed or as-of what date the values are.

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 a single efficient line with the topic front-loaded before a colon-separated content list; there is zero filler. It loses a point for being a verbless fragment, which makes it slightly less self-contained as a description.

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?

For a one-parameter, fully-annotated, read-only tool with an output schema present, the description covers the essentials: what entity it addresses and what data it returns. The remaining gaps — no sibling distinction from fund_holdings and no definition of 'last-quarter moves' — are real but minor for this simple tool.

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%: the ticker parameter already includes a type, examples (AAPL, BRK.A), and a description noting dots are allowed. With the schema carrying the full burden, the baseline of 3 applies; the description adds nothing about parameters.

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 names a specific resource ('One company as held by tracked funds') and enumerates the data content (holders, values, last-quarter moves), which distinguishes it from siblings like stock_earnings, stock_financials, and stock_insiders. It stops short of a 5 because it is a noun phrase with no explicit verb — 'get' appears only in the title — and it does not clearly differentiate itself from fund_holdings, which could plausibly cover the same 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 gives no guidance on when to call this tool versus alternatives; it never mentions siblings or exclusions. The closest rival, fund_holdings, is not addressed, leaving the agent to guess whether to use this tool or fund_holdings for a holdings query.

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