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

Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=false, so the safety profile is covered. The description adds behavior-relevant context the annotations don't carry: that fees are 'current' and the total is an 'estimate', signaling output is informational and approximate rather than a binding quote.

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 with zero filler: the first enumerates the payload, the second lists trigger phrasings. The most decision-relevant content (what the tool returns) is front-loaded.

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?

There is no output schema, so the description carries the burden of describing returns — and it does so item by item. Combined with two fully documented optional parameters and a read-only annotation profile, an agent has everything needed to call this correctly.

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 100%, so both parameters are already fully documented with units, defaults, and ranges, which sets the baseline at 3. The description's mention of daily storage and an estimated total lightly implies how days_until_pickup and ticket amounts feed the result, but adds no syntax or semantics beyond the 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?

The description names a specific situation (a car towed in New Orleans) and enumerates exactly what the tool returns: the tow-confirmation phone number, the City tow lot address and hours, current fees (tow, daily storage, boot), and a total estimate. This clearly separates it from siblings like find_parking or airport_parking.

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?

Three concrete trigger phrases ('my car got towed', 'where is the New Orleans impound lot', 'how much to get my car out') make the intended invocation context unambiguous. It does not name when-not-to-use or an alternative sibling, but no sibling covers a towed-vehicle scenario, so the routing is effectively clear.

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