Qrz Lookup

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

Annotations already declare read-only, idempotent, open-world, non-destructive behavior, so the safety profile is covered. The description adds genuine context beyond that: the external service dependency and the subscription gate that can limit returned fields, which an agent needs to interpret thin responses. It doesn't detail rate limits or error behavior, keeping it short of a 5.

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 tight sentences: the action and returned fields come first, the subscription caveat second. The field enumeration slightly duplicates what the output schema already conveys, but it still aids quick scanning.

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 values needn't be explained, annotations cover the safety profile, and both parameters are fully documented in-schema. The description's remaining job — external dependency and subscription caveat — is handled, leaving nothing an agent needs 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 coverage is 100%, with both 'persona' and 'callsign' documented in-schema including an example callsign. The description adds no further parameter meaning, so the baseline 3 is appropriate.

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 ('Look up a callsign on QRZ.com') and enumerates the returned fields (name, grid, DXCC, license class, QSL info, image), so an agent knows exactly what this returns. It does not explicitly contrast itself with siblings like qrz_dxcc or qrz_logbook_fetch, but the resource is distinct enough to infer separation.

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 important prerequisite — a paid QRZ XML Subscription is required for full fields — which tells the agent when results may be degraded. However, it never says when to prefer this over sibling tools (qrz_dxcc, qrz_logbook_fetch) or what happens without a subscription beyond 'full fields' being unavailable.

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