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

The annotations already declare readOnlyHint=true, and the description aligns by stating 'GET'. The description adds the REST method but little else, such as error behavior or authentication needs. For a simple read-only retrieval, this is adequate but not enriched beyond the structured metadata.

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 a single, concise sentence that immediately states the action, resource, and key parameter. It also includes the REST endpoint for reference without unnecessary filler. Every word earns its place.

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?

The tool is simple (one required parameter, no output schema), and the description is sufficient to understand its core function. It could mention the return payload shape, but given the simplicity of a single-person fetch, the description is nearly complete. A slightly stronger description might note that it returns the person object, but this is not a major gap.

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 input schema covers 100% of the parameter documentation, fully describing 'id' as a required integer. The description only repeats 'by its id', adding no new meaning. With this high schema coverage, the baseline score of 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?

The description clearly states the tool gets a single person (contact) by id, using a specific verb and resource. This distinguishes it from sibling tools like list_persons or search_persons, which operate on collections. The inclusion of the REST endpoint further clarifies the exact operation.

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 provides clear context: use this when you have a specific person id and need that single record. It doesn't explicitly mention alternatives like list_persons or search_persons, but the phrasing 'by its id' implies the use case and differentiates from those tools.

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