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

Annotations already declare read-only, idempotent, non-destructive, closed-world, but the description adds substantial context beyond them: the source record (public CFPB HMDA 2025, actions 1,2,3, loan_type 2), the scope limit to the 100 largest FHA lenders, the important base-size caveat that the denied share is computed on a larger base than the published denial rate and both are returned, plus a non-prediction caveat and license attribution. That is exactly the extra disclosure annotations cannot carry.

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 the answerable questions, then scope, then caveats and attribution — a sensible order with no filler sentences. It is dense and long-ish, and the five quoted example questions could be trimmed, but each block (answers / not-for / source / caveat) 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 no output schema, the description carries the return-shape burden and does so: five outcome shares plus the approved-not-accepted share of approvals, each with its receipt, for national or a single top-100 lender. Source, population filters, and interpretation caveats are all present, leaving nothing an agent needs before calling it.

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% and the single optional `lender` param is fully documented (name, slug or LEI; omit for national). The description corroborates the 'nationally or for one of the 100 largest FHA lenders' scope but adds no format or resolution detail beyond the schema, so the baseline 3 is appropriate.

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 verb and resource: returns the five HMDA ends of an application (originated, approved-not-accepted, denied, withdrawn, closed for incompleteness) as shares of actions 1-5, plus the approved-not-accepted share of approvals. It also disambiguates from the related but different published denial rate (22.1% of decisioned applications), so an agent can tell it apart from the denial-stat siblings 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?

The 'ANSWERS:' list gives five concrete question shapes that select this tool, and the 'NOT FOR:' clause explicitly excludes causal explanation, lender quality, and individual outcomes. It does not name the sibling tool an agent should use instead for the excluded questions (e.g. get_denial_reason_shares or get_lender_denial_stats), so routing is strong on when-to-use but not on alternatives.

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