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

Annotations already establish read-only, idempotent and non-destructive behavior, so the bar is lower; the description still adds genuine value by disclosing the returned metrics (loan sizes, time to fund, max LVR, rate ranges) and explicitly scoping output to category level with no lender named, plus the effect of passing lane.

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 dense sentences front-load the purpose and the parameter behavior, with the enumeration of criteria and the example earning their space. Slightly heavy on list-like detail, but nothing 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, return values need not be documented, and the description still covers scope, the optional-parameter effect, and output granularity. The one gap is the absence of any routing cue to the sibling tools.

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 goes beyond the schema by listing what a passed lane actually unlocks (security, LVR, trading history, ATO position, deal-breakers, documents, pricing, term) and showing a concrete example value.

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 and resource ('Lists the types of business finance Switchboard Finance arranges') and narrows the audience to self-employed Australians and ABN holders, which is far more specific than the tool name alone. It does not, however, contrast itself against siblings like check_fit or search, leaving the agent to infer the boundary.

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 gives usage for the optional parameter ('Pass lane for one type's full criteria') and an example payload, which implies the no-arg case lists categories. But it never states when to choose this tool over check_fit, search or fetch, and no exclusions are offered.

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