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

Annotations already cover the safety profile (readOnly, non-destructive, openWorld), and the description adds useful behavior: page size default, cursor-based pagination, and the identity semantics of line_id. It could still note ordering or whether tracking data is refreshed, but it goes beyond the annotations.

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 dense sentences, no filler, front-loaded with the returned row shape before pagination mechanics. Every clause carries information the agent needs.

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?

An output schema exists, yet the description still efficiently previews row contents, and it covers pagination and the cross-tool line_id linkage. For a read-only list tool with full schema coverage, nothing an agent needs to invoke it correctly is missing.

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%, so all three parameters (limit, cursor, portfolio_id) are already documented in the schema. The description's restatement of the page size and cursor mechanics adds little beyond the structured fields, 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 ('The aircraft in one portfolio') and enumerates exactly what each row contains (tail, make/model/year, value and change, tracking status, loan balance). This clearly distinguishes it from the singular get_portfolio_aircraft and from list_portfolios.

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 explains the pagination workflow (next_cursor, default 50 per page) and, importantly, that line_id is the handle used by the other portfolio tools, which tells the agent how to chain calls. It stops short of explicitly saying when to choose this over get_portfolio_aircraft or list_tracked_aircraft.

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