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

With no annotations provided, the description must convey the behavioral profile. It discloses core outputs and data sources, but does not address potential limitations, data update frequency, or how parameters like 'state' modify the result beyond the schema. It also implies a fixed 12-month history, while the 'limit' parameter allows customization, which could be slightly misleading.

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 deliver the essential purpose and key data points without fluff. The structure front-loads the main function and follows with concise output details.

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?

The tool has four parameters and no output schema, but the description covers the primary return contents (current value, YoY change, 12-month history). The schema's per-parameter documentation handles the conditional logic, so the description is reasonably complete for an AI agent to make a basic call, though it does not discuss result formatting or edge cases.

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?

The input schema has 100% coverage, so the description is not required to explain parameters; however, it adds meaningful context by naming the exact data sources behind the 'type' parameter (FRED MSPUS vs. Zillow ZHVI). It does not elaborate on 'limit' or 'state' beyond what the schema already provides, so it meets the baseline without significantly exceeding it.

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 clearly states a specific verb ('Get') with a resource ('US home price data'), identifies data sources (FRED MSPUS, Zillow ZHVI), and distinguishes itself from siblings like rental data or market indicators. It also outlines key output features (current value, YoY change, history), making the purpose unambiguous.

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 implies the tool is for home price queries and differentiates national vs metro levels, but it does not explicitly state when to choose this tool over get_market_indicators or get_rental_data, nor does it mention exclusions. The context is clear for a home-price-focused query, but there are no explicit alternatives or when-not-to-use cues.

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