bokio_vat_summary

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

Goes well beyond the readOnly/openWorld annotations by disclosing the ledger sign convention (debit positive, credit negative), that outputVat is negated, how netVat is derived, and when it is positive. It also warns that the figures are raw account totals rather than tax-return boxes, which prevents a costly misinterpretation.

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?

Every clause carries non-obvious information: the account ranges, the negation rule, the netVat formula, the interpretation caveat, and the sign convention. The core scope statement is front-loaded and there is 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?

An output schema exists, yet the description still supplies the accounting semantics an agent needs to read the numbers correctly. For a read-only, three-parameter aggregation tool this covers everything required to invoke and interpret it.

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 both date bounds and the companyId fallback already documented in the schema. The description only adds the loose phrase 'for a period', 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?

States a specific verb (Sum) plus the exact account ranges (2610-2659, 3000-3999) and the derived figures it computes. That precision distinguishes it from generic siblings such as bokio_account_balances and bokio_profit_and_loss without needing to name them.

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?

Usage is only implied: the caveat 'do not map to tax-return boxes' tells an agent this is for VAT balance inspection rather than tax filing, but there is no explicit when-to-use statement or named alternative for cross-checking VAT.

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