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

With no annotations, the description carries the full transparency burden. It discloses the calculation model (60/80/100 W/m² for different insulation levels) and the fact that running costs per full-load hour are included. It does not mention error handling or exact output format, but for a calculation tool this is reasonably transparent.

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 two concise sentences, bilingual, and front-loaded with the tool's purpose. It avoids redundancy and includes only the most essential information about inputs and outputs.

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 relatively simple calculation tool with no output schema and no annotations, the description adequately explains the purpose, calculation basis, and the additional cost output. It could be more explicit about the return structure, but it is sufficiently complete for an agent to understand the tool's behavior.

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% and the description adds little beyond repeating the schema's own parameter explanations. The description mentions the insulation standards and running costs, but these are already described in the schema for daemmung and strompreis_euro_kwh, so it does not meaningfully enhance parameter understanding.

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 that the tool provides the required heating power in watts for a room, based on floor area and insulation standard. It distinguishes itself from sibling tools by focusing on electric/infrared heating power and the specific calculation factors, though it lacks an explicit verb like 'calculate'.

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 gives useful context (for rooms, from area and insulation), implying when this is relevant. However, it does not explicitly state when to use this tool over alternatives such as btu_empfehlung, nor does it mention exclusions or prerequisites beyond what the schema lists.

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