IDM PV-Überschuss kommunizieren

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

Despite annotations indicating readOnlyHint=false and other hints, the description reveals non-obvious behavioral traits: the temporary override behavior ('überschreibt die E3DC-Vorgabe TEMPORÄR bis zum nächsten E3DC-Zyklus') and the requirement for cyclic writing. It also explains the resulting heat pump behavior. This goes well beyond the structured annotation data, which does not disclose these transient effects.

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 includes a warning and explanatory details, which are relevant and each sentence contributes value. It is slightly long but well-structured with a clear warning block and separated sections for args/returns. The front-loaded main sentence immediately states the purpose, and the rest supports it without excessive verbosity.

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?

Given that this is a single-parameter setter with a documented output (JSON confirmation), the description covers the core behavior, critical integration context (E3DC), and required usage pattern. It lacks some edge-case details like error handling or authentication, but for its complexity, it is reasonably complete.

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 already provides a clear description for pv_ueberschuss_kw (units, register, constraints). The tool description additionally explains the parameter's role in triggering heat production and emphasizes the cyclic requirement, adding operational meaning beyond the schema. Although the schema description is already strong, the description enriches the semantic context.

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's function: 'Schreibt den aktuellen PV-Überschuss an die IDM Wärmepumpe (Register 74).' This identifies the specific verb (schreibt), resource (IDM Wärmepumpe), and target register. It distinguishes itself from sibling getter tools and other setters by focusing on PV surplus communication.

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 provides critical usage context: it warns that the E3DC system writes this value automatically and that direct writes only temporarily override until the next E3DC cycle. It explicitly states 'Dieser Wert muss ZYKLISCH geschrieben werden – nicht einmalig!' This gives clear when-to-use and when-not-to-use guidance, though it does not explicitly name alternative tools.

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