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

Annotations already establish that this is a safe, read-only, closed-world lookup, so the safety bar is low. The description adds real behavioral context beyond that: the hedging 'the public FAQ may cover it' warns that a miss is possible, and the explicit prohibition on eliciting tax IDs, Medicare numbers, or payment details is a behavioral constraint not captured in the annotations.

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, no filler. The applicability condition comes first and the prohibitions follow, which is the right ordering for an agent deciding whether to call.

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 one-parameter lookup with full annotation and schema coverage, only two things matter: when to call and what not to send — both are present. The residual gap is that with no output schema, the description does not say what a successful return looks like or what to do when the FAQ has no matching entry, though 'may cover it' gestures at the latter.

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?

There is a single parameter with 100% schema description coverage, including length bounds and the sensitive-data prohibition, so the schema carries the load. The description's only additional note on the parameter is the same sensitive-data rule restated, adding no new meaning. 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?

The description identifies the resource as the public FAQ about SparkReady and household solar/battery loans, so the agent can grasp what is being queried. However, it never states a verb (search, look up, retrieve) and never distinguishes this from the numerous explain_* siblings (explain_solar, explain_loan_basics, explain_hesl) that cover overlapping ground, leaving the boundary unclear.

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 explicitly says when to reach for it ('when the question is about SparkReady or how household solar and battery loans usually work') and gives three concrete exclusions: do not use it to invent an answer, to assess an application, or to collect TFN/SSN/Medicare/bank/card data. What is missing is routing to a specific alternative — the agent is told what not to do but not which sibling to call instead.

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