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

Annotations already declare readOnlyHint, openWorldHint and idempotentHint, so the safety profile is covered. The description adds genuinely useful behavior — built-in fuzzy matching with concrete examples, ranked results with a total count, and the "names and codes, not the full record" coverage caveat — but says nothing about pagination or result ordering details beyond "ranked."

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 core purpose, then the fuzzy-matching examples, then the routing guidance. Five sentences that mostly earn their place, though the types/near sentence partially duplicates the schema and could be trimmed.

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?

No output schema exists, and the description compensates by describing the return shape (ranked matches with a total count, names and codes only, no full records). Combined with explicit routing to downstream tools, 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 q, near, limit, state, types and country are all already documented, including the cost tiers and enum values. The description's mentions of types and near largely restate the schema; its only added semantic value is characterizing what q accepts (misspellings, partial codes) and the ranked output shape.

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 (place) with the exact scope: partial name, misspelled name, or partial code. It explicitly frames itself as the resolver feeding zip_lookup, radius_search and distance, so it is unmistakable next to its siblings.

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?

"Reach for this FIRST when the place is vague, misspelled or partial, then pass the resolved code to zip_lookup, radius_search or distance" gives an explicit ordering plus named downstream alternatives. It also covers the when-not case implicitly by stating coverage is broad rather than deep.

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