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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's real contribution is the disclosure that figures are minimums, count only nameable companies, and that the answer reports coverage. That is meaningful behavioral context beyond the annotations, though it says nothing about rate limits or performance.

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?

Content is front-loaded (what it returns, then usage, then input semantics) and every clause carries information. The sentences are dense and clause-heavy, which costs a little readability, but there is no 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?

With an output schema present, return-format explanation is unnecessary, and the description still covers the aggregation scope, input forms, currency, and the important 'minimums / nameable-only' caveat. Complete enough for a nested-object, single-required-param 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 description coverage is 100%, so the schema already documents both parameters. The description restates the holdings-as-money behavior and the base currency default (USD), adding little beyond what the schema already conveys. Baseline 3 is appropriate.

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: aggregating the underlying companies a portfolio owns through its funds, with shares, overlapping names, and sectors. It explicitly distinguishes itself from measure_portfolio (full measurement) and asset_info (one fund), so an agent can select it without opening any 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?

It names the user question it answers ('what do I really own?') and routes to explicit alternatives: measure_portfolio for the full measurement, asset_info for a single fund. Both when-to-use and when-not-to-use are present.

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