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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is fully covered. The description adds only the raw endpoint path (GET /v1/Contacts/{id}), with no mention of not-found behavior, permissions, or response shape—essentially nothing beyond structured fields.

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 fragments with zero waste and the key fact (single contact by id) front-loaded. It is terse to the point of being skeletal, but nothing is padded.

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 simple one-parameter read tool with annotations covering safety, the description is minimally sufficient. It still omits what the returned contact contains and what happens on an invalid id, gaps an agent may care about when chaining calls.

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% and the single parameter contact_id is documented as "Jackrabbit contact id" with a positive-integer constraint. The description adds no meaning beyond that, so the baseline 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?

"One contact by id" states the resource and the single-record scope, which implicitly distinguishes it from jackrabbit_list_contacts. However, it never names the sibling or explicitly frames the verb, so the differentiation is inferred rather than stated.

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?

There is no guidance on when to use this versus jackrabbit_list_contacts or jackrabbit_list_authorized_contacts, nor any prerequisite such as needing a known contact_id. The agent must infer usage entirely from the name and schema.

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