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

With no annotations, the description carries the full burden and does so well: it discloses the dual net-income computation, the disagreement flag (e.g., merger pushdown accounting), attached merger events, and explicit data-quality behavior (does_not_reconcile_to_qbp labeling in specific quarters, 'nothing is forced to balance'). It omits auth/rate-limit context, but the operational behaviors that matter for interpreting results are covered.

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?

Front-loads what the tool returns before moving to inputs and caveats, and almost every sentence carries usable information. The reconciliation-statistics sentences (106 of 136 checks, 8 quarters) are dense and borderline over-detailed, slightly blunting conciseness.

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?

For a 4-param, no-annotation, no-output-schema tool, the description covers purpose, inputs, return semantics, data caveats, and sibling routing. Remaining gaps—output field names and date/quarter string formats—are modest given no output schema exists to explain returns.

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 must compensate; it explains cert as the FDIC cert number and clarifies the quarter-vs-start/end alternative with latest as default. It does not specify the string format for quarter/start/end (e.g., '2023-Q1'), which is a real gap for correct invocation, but it adds substantial meaning over the bare 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?

States a specific resource and scope: single-quarter net income for one FDIC-insured bank, naming the exact metric (official quarterly net income plus a YTD difference flag). It also names the sibling it is not for ('For credit unions use cu_quarter_income'), so an agent can distinguish it without opening a schema.

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?

Tells the agent exactly what inputs to supply ('Give the FDIC cert number and either one quarter (default latest) or a start-end range') and routes credit-union queries to cu_quarter_income. It does not spell out scope exclusions beyond that one alternative, but the use context is clear.

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