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

Annotations already establish readOnly/idempotent/non-destructive/closed-world, so the bar is lower. The description earns credit by disclosing what each comparison row contains – max loan size and rule, rate type, term, coverage test, extra costs, process, and cited regulation or HUD letter – which tells the agent the output's depth and authority.

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 sentences, front-loaded with the comparison scope, then the per-row content. Dense but every clause conveys distinct information; no filler.

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 read-only, single-optional-param comparison tool with no output schema, the description fully specifies the returned fields and their sourcing, so an agent knows exactly what it gets. Nothing needed to invoke correctly is missing.

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% and the enum values are self-explanatory, so the schema carries parameter meaning. The description adds no format or selection nuance beyond what the schema already says ('omit for all four').

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 ('side-by-side rules for financing') and enumerates the exact four programs compared (HUD 221(d)(4), bank loan, debt fund, 4% LIHTC with bonds). An agent can tell this apart from the sizing and market siblings without opening the 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 description makes the comparison use case evident, but it never names the alternatives (size_construction_loan, get_construction_market, get_build_timeline) or states when to pick this tool over them. Usage is implied rather than stated.

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