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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds genuine value beyond them by disclosing the per-call price (3¢) and the structural limitation that the chain terminates at GCCSA because LGAs are not strictly nested in SA4 — a behavioral constraint an agent could not derive from the schema or 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 compact sentences plus a price line, with the core capability front-loaded and no filler. The bolded price marker is slightly noisy formatting but the information itself is worth the space; the SA4 caveat is justified because it explains the chain's stopping point.

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 no output schema, the description should convey the shape of the returned geography chain, and it does so only at a high level (state + GCCSA). Combined with the total absence of parameter guidance, the definition is adequate but leaves real gaps an agent would hit on first call.

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 0% for the single parameter lga_name, so the description carries the burden of explaining it — and it says nothing about it. It does not state whether the name must match exactly, what format to use, or that lga_list can supply valid names, leaving an agent to guess at input validity.

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 the resource (the LGA's parent geography chain) and specifies its contents (state + GCCSA), which is more concrete than the title alone. It never names or contrasts with siblings like lga_list, lga_population, or sa4_profile, so an agent must infer the boundary from context rather than from an explicit statement.

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 only implied: an agent can infer this is the tool to call when it needs an LGA's upward geography mapping. There is no explicit when-to-use framing, no mention of prerequisites (e.g. obtaining a valid LGA name via lga_list), and no named alternative for related lookups such as sa4_profile or lga_population.

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