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

The description goes well beyond the annotations by disclosing critical behavioral traits: it caps at 5000 transactions per account and flags truncated:true, includes a provider_incident block explaining that data may be incomplete during incidents, and clarifies that granularity:'raw' is heavier. These details help the agent anticipate potential incomplete results and performance implications, adding significant value beyond the readOnly/idempotent 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 lengthy but information-dense; each sentence contributes meaningful details. It covers functionality, parameters, return values, edge cases, and usage guidance in a compact manner. While it could be broken into clearer paragraphs, it remains efficient for the tool's complexity and avoids redundancy.

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 the 9-parameter schema and absence of an output schema, the description must explain both inputs and outputs. It does this thoroughly: it describes the compact summary fields (total entradas, saídas, saldo_liquido, por_mes, top_despesas, top_recebimentos, by_account), the raw row behavior, the truncation flag, and the provider_incident block. It also covers optional behavior like bulk execution, making it highly complete for the tool's complexity.

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?

With 0% schema description coverage, the description takes on the burden of parameter semantics. It successfully explains item (connector_id, connector_name, or item_id), from/to as ISO dates, granularity (monthly vs raw), detail (rich/raw), and type (BANK/CREDIT). However, top_n is only implied through 'top_despesas/top_recebimentos' and item_id/item_ids are not individually clarified, leaving some ambiguity for the remaining parameters.

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: 'Consolidated cash-flow analysis for a whole bank CONNECTION over a period, in ONE call.' It uses specific verbs and resources, and explicitly distinguishes itself from siblings by noting it resolves accounts internally, so users don't need to call openfinance_list_accounts first. It also lists concrete use cases like 'análise anual/mensal', 'fluxo de caixa', and 'maiores gastos/recebimentos', making the purpose unmistakable.

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 detailed guidance on when to use the tool: it suggests using it for monthly/annual analysis, cash flow, and top expenses/revenues, and explicitly says to set granularity:'raw' only when itemized rows are needed. It also mentions the bulk support via item_ids, which is another usage scenario. However, it does not explicitly name alternative sibling tools like openfinance_list_transactions, so the exclusion is only implied.

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