get_cash_flow_summary

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It discloses the non-obvious sign convention (inflows positive, outflows positive, net = income − spending), which adds value. However, it lacks disclosure of other potentially important behaviors such as data freshness, currency, or whether transfers are excluded (though the schema notes a default), leaving some ambiguity.

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 concise and front-loaded with the core purpose. The first two sentences are slightly redundant ('Monthly income vs. spending' and 'Answers ...'), but the third sentence adds essential sign convention detail. Overall, it is compact with minimal waste.

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?

Since there is no output schema, the description should explain what the response contains. The phrase 'Monthly income vs. spending' is ambiguous about whether the result is a monthly breakdown or a single aggregate over the date range. This omission could lead an agent to incorrectly assume the return format, making the description inadequate for a tool with multiple parameters and no structured output documentation.

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?

The schema covers 100% of the parameters with descriptions, so the baseline is 3. The description does not significantly augment the parameter semantics; it only implies that the date range and cash accounts are relevant. It does not elaborate on how excludeTransfers affects results or how accountId scopes the data beyond what the schema already provides.

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: summarizing monthly income vs. spending for cash accounts. It uses a specific verb and resource, and the sign convention detail further clarifies exactly what is measured, distinguishing it from sibling tools like get_account_balances or get_savings_rate.

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 implies the use case ('Answers how much did I earn and spend? over a period') but does not explicitly state when to use this tool over alternatives or mention any exclusions. There is no comparison to sibling tools that might also relate to cash accounts, so the guidance is implicit rather than explicit.

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