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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds useful behavioral context: it is a 'Free geography utility' with 'No payment required', and it handles a 'bounded list' of references, implying rate/volume limits. It also explains the internal resolution chain (loc_id). This adds value beyond the annotation, though it does not disclose error handling, pagination, or exact output format, which are not required given the annotation coverage.

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?

The description is two sentences with no wasted words. The core action is front-loaded, followed by mechanisms and examples. The final sentence about payment is a brief differentiator. It is tight, informative, and well-structured.

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?

Given the tool's complexity (11 parameters, batch mode) and lack of an output schema, the description is reasonably complete. It explains the purpose and typical workflows, which is enough for an agent to invoke it correctly. However, it does not specify return format or error/edge-case behavior, but the extensive schema descriptions cover parameter semantics. Given that the tool is read-only and the schema is detailed, the description suffices.

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 adds meaning by clarifying the single vs. batch modes ('one reference, or a bounded list of references') and giving examples of valid from/to systems within workflows. It also implies the 'limit' and 'min_share' parameters refer to ranked output, aligning with the schema. This is modest extra context that complements the 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?

The description states a specific verb ('Converts'), a clear resource ('geographic reference system'), and the scope (one reference or a bounded list). It explicitly explains the mechanism (resolving through DaedalMap loc_id: X -> loc_id -> Y) and provides concrete workflow examples (ZIP/ZCTA to NWS fire zones, NWS zone to counties, county to overlapping ZCTAs). This clearly distinguishes it from sibling tools like resolve_reference, which likely handles single-reference resolution.

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 explicit use cases: 'Use this for workflows like ZIP/ZCTA to NWS fire zones, NWS zone to counties, county to overlapping ZCTAs, or any future catalog-backed crosswalk.' This tells an agent when to apply the tool. However, it does not explicitly say when not to use it or name alternative tools, relying on the workflow context to implicitly separate it from siblings. So it is clear but lacks explicit exclusions.

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