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

Annotations already declare this as a read-only, idempotent, non-destructive, open-world lookup, so the safety profile is covered. The description adds genuinely new behavior: at most 5 matches are returned, each carrying a house id, and the agent should disambiguate with the user rather than guessing.

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?

Three short sentences, each doing distinct work: what it finds, what it returns, and how to handle ambiguity. The purpose and the disambiguation rule are front-loaded with no filler.

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 no output schema, the description carries the burden of describing returns and does so at a high level (up to 5 matches, house id). It does not say what happens on zero matches or what other fields a match contains, which a caller might want before passing the id onward.

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 single 'address' parameter already documents format, Bavaria constraint, and length bounds. The description only restates that lookup is by address, adding no syntax or fallback detail beyond the schema, so the baseline 3 applies.

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?

Names a specific verb and resource ('find a building by its address') and scopes it geographically to Bavaria and functionally to the solar roof check, which distinguishes it from downstream siblings like plan_roof or check_service_area. It stops short of explicitly naming which sibling to use instead, so it is clear but not fully differentiated.

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 a concrete workflow rule: if several matches come back, ask the person which one before planning — this implicitly places the call before planning steps. It lacks an explicit exclusion such as when to use check_service_area instead, so it is clear context rather than full when/when-not guidance.

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