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

With no annotations, the description should disclose all behavioral traits. It provides the formula and units but omits details like error handling, the default efficiency value, and the missing density parameter (mentioned but not in schema). This undermines transparency.

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?

The description is brief (two sentences) but includes an inaccurate input list. The formula is useful, but the erroneous 'density' detracts from conciseness.

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?

For a simple calculation tool with output schema, the description lacks clarity on inputs (density discrepancy) and does not explain the output format beyond 'Returns kW'. It is incomplete and potentially misleading.

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?

The input schema describes all three parameters (100% coverage). The description adds formula context but incorrectly includes 'density' as an input, contradicting the schema. This misleads the agent about required inputs.

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?

The description clearly states the tool computes pump power, provides the formula, and specifies usage for fluid system design. However, it incorrectly lists 'fluid density' as an input, which is absent from the schema, causing confusion.

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?

The description says 'Use for fluid system design' and points to list_bundles for related calculators, providing some context. But it does not specify when not to use this tool or alternative approaches.

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