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

Annotations already cover the safety profile (read-only, idempotent, closed-world). The description adds genuinely useful behavioral context beyond them: the data is free, sourced from FFIEC filings, and every output number is labeled as filed, derived, or assumed. That provenance disclosure is exactly the kind of context an agent cannot get from annotations or schema.

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?

Two tight sentences with the core purpose front-loaded and provenance details second. The semicolon-chained second sentence is dense but every clause (free, FFIEC-sourced, filed/derived/assumed labeling) earns its place.

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?

With four fully documented parameters and no output schema, the description should do more to characterize the result set. It says outputs are labeled by provenance but does not describe the scenario table the renewalRatePercent parameter references, leaving the return shape only partially understood.

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 description coverage is 100%, so parameter meaning is already well documented and the baseline is 3. The description's references to renewal assumptions, replacement funding, and tier-specific costs loosely map to the parameters but add no formats, units, or constraints beyond 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 description names a specific analytical task: measuring time deposits maturing or repricing within a year and testing renewal/replacement assumptions against tier-specific costs. That is far more specific than the title alone. It does not, however, contrast itself with related siblings such as nim_rate_shock or margin_capture, so an agent must infer the boundary.

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 implied by the scenario language ('test explicit renewal and replacement assumptions'), which tells the agent this is a what-if refinancing tool. There is no explicit when-to-use versus when-not-to-use guidance and no named alternative among the sibling tools.

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