Resolve a place name to a geoid

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds genuinely new behavior — it returns ranked candidates, deliberately does NOT auto-pick, and explains the ambiguity risk (duplicate county names, wrong-grain picks). It stops short of describing candidate payload shape, but the output schema exists for that.

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 purpose, then the no-auto-pick behavior, then the routing escape hatch, then args. Every sentence earns its place, though the Washington County illustration is slightly verbose and the mid-paragraph 'ASK' instruction interrupts the flow.

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?

An output schema exists, so return shape needn't be explained, and the description still tells the agent how to use results (name the chosen place and geoid in the answer). For a two-parameter read-only resolver, nothing an agent needs to call it correctly is missing.

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%, so the description carries the load, and it does: it defines 'name' with example formats ('Cook County', 'Chicago Public Schools') and the NCES-naming convention, and enumerates the three legal 'geo_level' values. It adds real meaning beyond the bare schema, though it does not state what happens when geo_level is omitted.

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+resource+outcome: 'Find the state, county, or school-district geoid used by get_data.' It also implicitly distinguishes itself from the get_data sibling by identifying itself as the name-to-geoid resolution step that feeds it.

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?

Explicit routing rules: skip this tool entirely for statewide queries and use get_data(state="12") instead, and ASK the user when candidates span geo levels. Both the when-to-use and when-not-to-use cases are named with concrete conditions.

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