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

readOnlyHint already declares this a safe read, so the bar is lower. The description does add a useful behavioral detail not in the structured fields — a fixed page size of 20 — plus the filter_val dependency, but it says nothing about ordering, rate limits, or what a page of results contains.

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?

Dense and front-loaded: the resource and page size come first, then the filter set, then the endpoint. No filler sentences, though the inline filter list is long and slightly duplicates the schema enum.

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, zero-required-parameter list tool with full schema coverage and no output schema, the description covers the essentials: what it returns, pagination size, and filter semantics. Only the sibling-choice question is left unanswered.

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%, so all three parameters are already documented, including the '> 50' example for filter_val. The description largely restates the enum and the filter_val example, adding no new semantics beyond the schema; baseline 3 applies.

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 and resource ('List business customers') and names the underlying endpoint, so the agent knows exactly what it retrieves. It doesn't explicitly distinguish itself from near-siblings like ezrentout_list_customers or ezrentout_get_business, but the 'businesses' resource is clear enough to route on.

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?

It enumerates the valid filter values and flags the one case needing extra input (completed_orders needs filter_val), which is genuine usage guidance. However, it never says when to reach for this instead of ezrentout_list_customers or ezrentout_get_business, and gives no exclusion guidance.

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