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

Goes far beyond the readOnly/idempotent/destructive annotations by disclosing connector-dependent balance semantics, balance_notice, provider_incident, identity_notice, and lagging bankData fields. No statement conflicts with the annotations.

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 long but well organized, opening with the core return value and then layering caveats. It is dense and occasionally wordy, though most sentences earn their place given the complexity of Open Finance edge cases.

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?

Despite no output schema, it describes the main fields and the notice blocks, explains authoritative vs auxiliary data, and gives dedupe instructions. An agent has enough context to call the tool correctly and to avoid misinterpreting returned values.

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 0%, so the description carries the parameter-documentation burden. It explains item omission vs presence and item_ids bulk execution, but it does not explicitly define item_id or describe how type filters results, leaving those two parameters to be inferred from the schema.

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 first line names a specific verb-resource pair ('Returns accounts') and enumerates the exact account types and fields returned (balance, number, type, subtype, bankData, creditData). It also distinguishes the tool's role from related tools by noting that standardized bill data belongs to openfinance_list_credit_card_bills.

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?

Explicitly explains when to omit item for cross-bank aggregation versus pass item for one bank, and when to use openfinance_list_credit_card_bills instead for standardized open-bill amounts. It even gives handling guidance for stale fields (force sync) and for notices, covering both selection and interpretation of results.

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