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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description earns credit by adding runtime behavior instead: unscoped queries take ~2 minutes, and it discloses the source report (ReportWriter RW 107) and the computed fields. Missing only things like rate limits or connection requirements.

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 definition ('Available (vacant) inventory + exposure by property and unit type') and every following sentence carries information – the report source, the example queries, the scoping/time note, and the alternative. Slightly dense but no waste.

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?

An output schema exists, so return values need no prose, and the description still supplies the report identity, scoping/time guidance, and the sibling disambiguation. The remaining gap is parameter-level semantics (top_n, property_ids format), which is a real but secondary omission.

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 0%, so the description must carry parameter meaning, but it only partially does: it explains that portfolio/property scoping is a performance tradeoff, yet leaves top_n and the format of property_ids (comma-separated IDs? names?) entirely undefined. Partial compensation over a bare schema.

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+resource (analysis of available/vacant inventory and exposure) scoped by property and unit type, and explicitly distinguishes itself from the sibling analyze_vacancy ('For a unit-level vacant list use analyze_vacancy'). It also names the underlying report (RW 107), which pins down exactly what is computed.

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 concrete trigger phrases ('what's our available inventory / exposure', 'vacancy rate by property', 'which parks have the most vacant lots'), names the alternative (analyze_vacancy) with the condition that selects it, and explains when to scope (portfolio/property set for speed). This is explicit when-to-use and when-to-use-something-else guidance.

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