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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds provenance (FFIEC HMDA LAR) and the aggregation dimensions, but says nothing about reporting lag, coverage years, or the granularity of the returned series.

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 resource and its contents front-loaded and provenance in parentheses. Nothing is wasted, though 'book' is mild jargon that could read as ambiguous to an agent unfamiliar with the term.

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 no output schema, the description carries the burden of describing return contents, and it does list the measure families and the year/state breakdown. It still leaves open what time span is covered and whether volumes are in raw USD, which matters for interpreting results.

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 100% with an example value and a clear definition of rssd_id as a Federal Reserve RSSD id, so the description need not repeat it. 'Per-bank' reinforces that the identifier selects one institution rather than a peer set.

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 concrete resource (per-bank HMDA mortgage-lending book) and enumerates its contents: applications, originations, denials, and USD volumes, sliced by activity year and state. 'Per-bank' implicitly separates it from aggregate siblings such as nonbank_mortgage_states, but no sibling is named explicitly.

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 only implied: an agent can infer this is the tool for mortgage-lending activity for a specific institution identified by RSSD id. There is no explicit when-to-use or when-not guidance, and no pointer to mortgage_performance or nonbank_mortgage_states for adjacent needs.

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