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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds value beyond that by disclosing the 100-address cap and the batching behavior (one pass versus looping), which is behavioral context the annotations don't carry. It stops short of discussing rate limits or partial-failure behavior on a mixed-result batch.

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, zero filler. The capability statement comes first and the disambiguation against the sibling is front-loaded as the decision rule, which is exactly where an agent needs it.

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 no output schema, the description takes on the burden of describing return values and does so explicitly (match status, standardized address, coordinates, state/county/tract/block FIPS). Combined with the 100-address cap and the sibling routing rule, an agent has everything needed to call it correctly.

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 the schema already documents the address object fields, the id echo, and the vintage/benchmark defaults. The description only restates the 100-item maximum already present in the schema and adds no syntax guidance for vintage or benchmark. Baseline 3 is appropriate when the schema does the heavy lifting.

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 (geocode US addresses), explicit scope (up to 100 per call), and enumerates the return payload (match status, standardized address, coordinates, FIPS codes). It also names the sibling census_geocode_address, so an agent can differentiate without opening either schema.

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?

Gives an explicit selection rule: use this instead of looping census_geocode_address when you have a list. This names the alternative sibling and the condition that selects it, leaving nothing to inference. No explicit 'when not to use' is needed since the batch vs single distinction is fully covered.

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