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

Annotations already cover the safety profile (readOnly, idempotent, openWorld), and the description adds a genuinely non-obvious data-semantics caveat: 'Position values are reported holdings, not money flows.' That prevents misinterpreting the returned numbers. It still omits aggregation method, units, and default-quarter behavior, keeping it out of the top band.

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?

Two short sentences, zero filler, with the core scope stated first and the interpretation caveat second. Nothing is repeated from the title or schema.

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 two-parameter read-only tool with no output schema, the description gives the gist of what comes back ('aggregated buy/sell picture', 'position values') but not the shape of the aggregation, which quarter is defaulted, or how many periods are returned. Adequate but with clear gaps.

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 are already documented with examples (AAPL, 2026-Q1). The description adds no syntax, format, or defaulting detail beyond the schema, so the 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?

States a specific verb and resource ('aggregated institutional buy/sell picture') scoped to one stock and one quarter, which naturally separates it from the sibling list tools such as institutional_list_holdings and institutional_get_fund_holdings. It does not name those siblings explicitly, so it falls just short of full differentiation.

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 never says when to use this tool versus the many sibling institutional/filings/insider tools, nor does it mention prerequisites or the default behavior when 'quarter' is omitted. Usage must be inferred entirely from the name and scope phrase.

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