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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered and the description carries a lower burden. Beyond that it usefully discloses the depth gradient (deep rules for five states, baseline elsewhere) and one concrete figure ($15,000 NC 1st Home Advantage). It does not state that amounts are estimates subject to lender/program approval, nor whether the result is a pass/fail plus award figure.

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?

A single dense sentence with the verb and scope front-loaded, and every clause (state list, national baseline, the NC dollar figure) adds informational value. The parenthetical program enumeration is heavy but not padded; nothing is repeated from the title.

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 9 parameters, no output schema, and a rules-engine behavior, the description should say more about what comes back (eligibility verdict, award amount, limiting factors) and about the authority/currency of the state rules it applies. It correctly covers geographic coverage and the baseline fallback, which is the biggest completeness risk, but leaves return-shape expectations entirely to inference.

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% with 3 enums fully documented, so the schema already explains state, homePrice, buyerStatus, creditScore, income, liquid cash, lien structure, first mortgage program, and non-housing debt. The description adds no parameter-level meaning — notably it never explains how secondLienStructure interacts with the state defaults, which is the one thing the schema leaves genuinely ambiguous.

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 verb+resource pair ('Evaluates eligibility and estimated assistance amounts for state HFA programs') and enumerates exactly which state programs are covered deeply (TX TSAHC/TDHCA, FL, CO CHFA, GA Dream, NC NCHFA) versus the national baseline fallback. That scope is far more precise than any sibling, though it never explicitly contrasts itself with calculate_mortgage_affordability or evaluate_loan_readiness_score, 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 only implied: the program list signals 'use this when a buyer wants down payment assistance in one of these states.' There is no explicit when-to-use statement, no prerequisites (e.g., income limits or first-time-buyer requirement checks), and no named alternative among the six sibling tools that handle affordability, DTI, or loan readiness.

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