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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds the historical/dated nature of the result and the watchlist scoping, but says nothing about how many snapshots are returned, date-range limits, or auth requirements.

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 sentences with the resource stated first and use cases second; no filler. Slightly terse given the gaps elsewhere, but every clause earns its place.

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, so return values need not be described, and the read-only annotation covers safety. For a single-parameter read tool the description is nearly sufficient, lacking only guidance on result volume or time coverage.

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 0% for the single tracked_aircraft_id parameter, so the schema supplies no meaning. The description partly compensates by framing the input as a 'watchlisted tail,' but it doesn't clarify the ID's format or provenance.

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 (get) and resource (historical valuation snapshots for a watchlisted tail), with the added qualifier that they are dated value points. It is distinguishable from value_aircraft and list_tracked_aircraft, though it doesn't explicitly name those siblings.

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 three concrete use cases (value trends, portfolio appreciation/depreciation, collateral monitoring), which implies when to reach for it. However, it never says when NOT to use it or names an alternative such as value_aircraft for a current valuation.

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