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

Annotations already cover read-only/idempotent/non-destructive, and the description adds genuinely new behavioral context: the report window 'starts when the youngest holding starts' and amounts are converted into base currency. It stops short of describing report length or pagination, but that is minor given the annotation coverage.

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?

Purpose is front-loaded and the whole thing is four tight sentences. The prose is a little flowery ('make the report speak in money'), which costs a point, but nothing is redundant.

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?

Output schema exists so return values need not be spelled out, and both parameters plus the window-start behavior and currency handling are covered. The only soft spot is that the actual contents of the numbered report are described only abstractly.

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% and already documents base-currency defaults and the weights-vs-amounts semantics of holdings. The description largely restates these ('amounts in the base currency (default USD)'), adding little beyond the schema, so the 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?

States a specific artifact (a written, numbered F1/F2 report) on a single resource (one portfolio) and explicitly distinguishes itself from measure_portfolio, which returns 'this same report together with structure, look-through and crises'. An agent can tell exactly what this produces versus its closest sibling.

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 the selection condition ('For a reader who wants something to quote or keep') and names the alternative (measure_portfolio) that returns a superset. The when-to-use and the competing option are both explicit.

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