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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered. The description adds little beyond that: the default ZIP/radius and the 'strict' partial-coverage behavior and Census geocoding note are all already present in the schema descriptions, and nothing is said about pagination or result ordering across the mixed namespaces.

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, front-loaded with purpose then the origin-selection rule and default. No filler, no restatement of the title, and the most operationally important constraint (one origin) appears before the default values.

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 12-parameter, all-optional search with no output schema, the description covers what is searched, how to anchor the search, and the fallback default. It leaves unaddressed what the response looks like when multiple namespaces are combined and how 'limit' interacts with paging, which keeps it from a 5.

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 effective baseline is 3, and the description clears it by stating a cross-parameter constraint the flat schema does not express: choose one origin form (zip, lat+lng, address, or city+state). This is genuine added meaning for a 12-parameter, zero-required schema where otherwise nothing forces a single origin.

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 (search) and resource (Datamart) and enumerates the covered entity types: public library branches, public schools and colleges, and government services, plus radius scope. It is clear this is a cross-namespace search rather than a single-domain one, but it never names the siblings (libraries_search, education_search, gov_services_search) that cover the same domains individually, so the agent must infer the differentiation from the listed namespaces.

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?

The description gives an operational rule — supply exactly one origin among zip, lat+lng, address, or city+state — and states the default (ZIP 95032, 20 miles). It offers no explicit when-to-use/when-not guidance versus the per-domain siblings, so a caller cannot tell from the description alone whether to use this aggregate search or a targeted one.

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