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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description earns credit for behavior-relevant context beyond that: rules are 'current,' cite ML 2025-03, carry a primary source URL per rule, and include live counts pulled from HUD's file — useful signals about freshness and provenance.

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-loaded with the resource and its scope, then a dense but purposeful enumeration of covered rule types. The parenthetical code list and value notation are compact; no filler sentences, though it is close to list-dumping.

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 single-optional-parameter read tool with no output schema, the description discloses the returned facets (rate tiers, term, MIP, prepayment, fees, commercial limits, source URLs) and the aggregate mode. The coverage is strong; only the distinction from sibling lookups is left unstated.

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?

One optional parameter with a fully enumerated set of program codes, so the schema covers the value domain. The description still adds meaning by naming the codes inline and explaining the omit-for-all-summary semantics, which the schema does not state.

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 content set: current HUD multifamily program rules, with an explicit list of programs covered and the rule domains returned (LTV/LTC, DSCR, term, MIP, prepayment, Davis-Bacon, fees, commercial limits). It is clear what the tool yields, though it does not explicitly contrast itself with siblings like statutory_limit or size_223f that also touch program parameters.

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 only usage instruction is 'Omit program for the summary of all,' which explains the optional-parameter behavior but nothing about when to pick this tool over get_loan, hud_stats, size_223f, or statutory_limit. The agent must infer the boundary from the description's content list.

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