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

Annotations already declare readOnlyHint=true, openWorldHint=true, destructiveHint=false, so safety is covered. The description adds no behavioral context beyond annotations — no notes on freshness of valuation, auth requirements, or staleness of tracking status — leaving the description with nothing beyond a payload inventory.

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?

A single front-loaded sentence with no filler. It is efficient, though it spends its whole budget enumerating return fields, which the output schema already covers.

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, the return-value list is largely redundant, and the safety profile is fully covered by annotations. What remains missing is the guidance an agent actually needs — when to call this versus list_portfolio_aircraft or get_portfolio_positions.

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 both parameters (line_id and inflation_base) are documented in the schema with useful provenance and format hints. The description contributes no additional parameter meaning, 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 the resource precisely: a single portfolio aircraft ('One portfolio aircraft in full'), which implicitly contrasts with the plural sibling list_portfolio_aircraft. It does not name the retrieval verb or explicitly route against the list tool, but the singular scope is unambiguous.

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?

No when-to-use guidance, no mention of the sibling list_portfolio_aircraft as the way to obtain line_id, and no statement of prerequisites or when this differs from get_portfolio_positions. The only hint is that line_id provenance lives in the schema, not the description.

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