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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds substantial behavior beyond them: exactly-one-of input constraint, an ambiguous-result error with choices, link provenance (GovDir directory, checked on a schedule, verified_status/verified_at), the authority caveat that the office has final say, and an explicit prompt-injection warning about treating returned text as data.

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?

Front-loaded with the purpose and use-first trigger, and every sentence carries information (input constraint, ambiguity behavior, provenance, safety). It is a single dense paragraph rather than clearly segmented guidance, which makes it slightly harder to scan than it could be, but there is little waste.

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 6-parameter, open-world resolution tool with an output schema, the description covers what an agent needs: input combinations, disambiguation behavior, provenance/verification semantics, authority caveats, and injection safety. Return-shape detail is partly redundant with the output schema but not harmful.

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 baseline is 3. The description does add one piece of meaning the schema cannot express - the mutual exclusivity of address vs lat/lon vs place+state vs jurisdiction_id - but it offers no additional format or syntax detail beyond the already thorough schema descriptions.

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: returns the jurisdiction chain (state, county, town/township, city) with jurisdiction_id values plus the responsible body, office and official pages for each function. It explicitly clarifies that the responsible body is often a city/town/township rather than the county, which distinguishes its output from a generic directory lookup like search_directory.

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 a clear trigger ('Use first when the user names a US address, a point, or a place') and a recovery path for ambiguity (re-ask with lat/lon or a jurisdiction_id). It does not name sibling alternatives (search_directory, find_official_resource) or state when not to use it, so the routing guidance is strong but not complete.

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