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

Annotations already declare readOnly, idempotent and non-destructive, so safety is covered. The description adds real behavioral context beyond that: it discloses that responses include documents usually needed, deal-breakers and an expected callback time, and it clarifies the output is general information rather than a credit decision or advice.

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?

Purpose and scope are front-loaded in the first sentence, followed by the category list, the derived-check explanation and a concrete example. It is on the dense side, but each element (categories, example, disclaimer) does useful work, so little is wasted.

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?

With an output schema present, the description needn't detail return values, and all 10 parameters are schema-documented. It supplies the qualifying context (what triggers a fit, what comes back in general terms, and the advice disclaimer), making it complete enough to invoke correctly, with only the sibling-routing gap remaining.

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 the baseline is 3, but the description adds meaning by grouping amount, property value, timing and trading history and explaining what they are checked against (loan size, LVR, time to fund), implying how existing_debt and property_value combine. It stops short of fully specifying every parameter's interpretation.

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 states a specific verb (checks) and resource (an Australian business owner's finance need) and spells out the finance categories covered, so an agent immediately knows what this tool qualifies. It also distinguishes itself from siblings like list_products and request_callback by framing itself as a fit-check rather than a lookup or submission.

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?

Usage is strongly implied through the worked example and the mention of returning a callback time, which positions this as a pre-qualification step ahead of request_callback. However, it never explicitly says when to use this versus list_products or search, nor are there stated exclusions, leaving the routing to inference.

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