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

No annotations are provided, so the description carries the full burden. It discloses the historical HMDA 2025 source, the actions/loan_type filters, the peer-adjusted nature, the minimum-cell rule, and explicitly states 'Not a prediction about any individual application.' This is strong for a read-only query, though it does not define the minimum-cell rule or the exact output format.

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 labeled blocks (ANSWERS/PARAM/RETURNS/NOT FOR/Historical) front-load the most important selection information and every clause adds value. It is somewhat dense and telegraphic but not padded.

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 one-optional-param tool with no output schema and no annotations, the description explains what is returned, for which lenders, from which source, and what it is not. It lacks a precise output-shape definition and does not define peer-adjusted, but it is sufficient for selecting and invoking the tool.

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%; the schema already documents lender name/LEI and the omit-to-list-all behavior. The description adds 'slug' as an accepted form but mostly repeats schema content, 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 how that lender's peer-adjusted denial gap changes across published cells...' and answers three concrete questions. The NOT FOR clause helps distinguish it from sibling prediction and denial-stats tools, even though no sibling is named.

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?

Provides explicit when-to-use guidance through the ANSWERS question list and explicit when-not-to-use guidance via 'NOT FOR: suppressed small cells, or any individual prediction.' It does not name specific sibling tools as alternatives, so it falls just short of the top bar for routing guidance.

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