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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety and determinism are covered without the description. The description adds that inputs are object mass/volume plus fluid density and that a float/sink verdict is produced, but says nothing about unit handling, the default fluid, or edge cases like zero volume.

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?

Four short sentences, front-loaded with the purpose before inputs, outputs and the cross-reference. Slight filler in the trailing list_bundles pointer, but overall tight.

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 values need not be explained, and annotations carry the safety profile; the description covers purpose, inputs and result shape. It is only short on the default-fluid assumption and unit conventions, which matters for a computation 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% and all three parameters carry their own unit documentation, so the baseline is 3. The description repeats 'object mass/volume, fluid density' without adding anything the schema lacks, notably that fluid_density defaults to 1000 (water).

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 (compute) and resources (buoyancy force, displaced volume, floating analysis) and anchors the method with '(Archimedes)'. No sibling in the list covers buoyancy, so the tool is unmistakable once matched against the catalog.

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?

'Use for physics or shipping' gives a loose domain hint but no when-not conditions, prerequisites, or a named alternative to compare against. The pointer to list_bundles is a discovery aid, not usage routing.

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