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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds the supported unit scope but nothing about precision, rounding, or edge cases (e.g., negative pressures), which is the kind of extra context this dimension rewards.

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?

Compact and mostly front-loaded, but the unit list merely duplicates the enum values and the 'Returns: {original}' fragment is an unresolved template placeholder that carries no information.

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?

The output schema exists so return values need no prose, but the description still ships a broken return placeholder and a unit list inconsistent with the actual enum. The unit mismatch is a real completeness gap that could cause failed calls.

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 the schema already documents all three parameters and their enums. Worse, the description advertises kPa, MPa and torr, which are NOT in the from_unit/to_unit enums, so it actively misleads the agent about accepted inputs and adds no correct semantics beyond the schema.

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 ('Convert pressure between...') with the supported unit set, so the operation is unambiguous. However, it does not distinguish itself from the sibling 'convert_pressure' (nor from unit-conversion siblings like calculate_power_unit_convert), so an agent cannot tell from the text which pressure-conversion tool to pick.

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 domain contexts ('engineering, weather, medicine') and points to list_bundles for related 'conversions' calculators, which is mild routing help. But it offers no when-to-use vs when-not guidance and never addresses the overlap with convert_pressure, leaving selection to inference.

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