Calculate a Swedish monthly mortgage cost

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

Discloses key behaviors: no network call, uses Swedish amortisation rules (amorteringskrav, debt-ratio surcharge), includes ränteavdrag tax deduction. Annotations (readOnlyHint, idempotentHint) are consistent and the description enriches them with algorithmic details.

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?

Fairly concise for a complex tool; the core purpose is front-loaded. A few extra details (e.g., 'BRF fee (avgift)') are useful but could be slightly trimmed. Still highly effective.

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?

No output schema, but the description fully explains the return value (monthly cost breakdown with gross/after-tax). All parameters are covered, and the context (local-only, Swedish rules) is complete for an agent to use this tool correctly.

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% with descriptions. The description adds beyond schema by clarifying defaults (down_payment_percent defaults to 15% legal minimum) and the effect of gross_yearly_income (enables +1% surcharge). This meaningfully aids 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 uses a specific verb ('Calculate a Swedish monthly mortgage cost') and explicitly details what it computes (interest, amortisation, BRF fee, operating cost, gross/after-tax totals). It is distinct from all sibling tools, which are search, listing, or location tools.

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?

Implies usage context: Swedish mortgages only, local amounts. No explicit when-not-to-use or alternatives, but no sibling calculator exists, so the differentiation is clear. A 4 reflects minor room for explicit exclusion statements.

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