Get a marktplaats.nl seller profile

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

Annotations already declare read-only and open-world; the description adds that the profile is public (no auth needed) and that the ID comes from search results, which helps the agent understand the source and safety. It does not detail error handling, but that's beyond what's expected here.

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 short sentences, front-loaded with the action and resource, and the second sentence adds purpose without redundancy.

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 read-only profile fetch with only one required parameter, the description provides enough context on what the tool does, where the ID comes from, and how the result can be used. Without an output schema, it could explain return fields, but the purpose makes the presence of profile information sufficient.

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?

The schema already fully describes both parameters with 100% coverage, including the numeric seller id and optional seller name. The description's mention of 'numeric seller id' reinforces the schema but adds little new meaning, so baseline of 3 applies.

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 clearly states the tool fetches a seller's public profile by numeric seller id, and differentiates it from listing-related siblings by focusing on seller information. It also explains the use case of determining private vs shop, which further clarifies purpose.

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?

Provides a clear context: useful for judging seller type after obtaining the ID from search results. It does not explicitly name alternatives or when-not-to-use, but the context is sufficient to infer when to call it.

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