Get service item

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile needs no repetition. The description adds value the annotations cannot convey: the response includes custom field names intended for use in a subsequent request, which tells the agent this call is a lookup step and explains the key payload content. It stops short of noting what happens when display_id is invalid.

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?

A single sentence, front-loaded with the action and resource, with the one piece of non-obvious payload information appended. Nothing is wasted and nothing needs to be re-read.

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 need no explanation, and the read-only annotations cover the safety posture. The description still provides the practical reason to call this tool, which is enough for a 1-parameter lookup. The only gap is the absence of guidance on routing between this tool and the service-item search and list siblings.

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 a single required parameter, and the schema already documents display_id as "Service item display_id." The description adds no format, range, or sourcing guidance for that identifier, so the baseline 3 is correct when the schema carries the parameter documentation.

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 ("Get a service item") and adds what the payload contains: form fields and custom_fields names. That is more than a restatement of the title. However, it doesn't explicitly distinguish itself from the sibling retrieval tools list_service_items, search_service_items, or get_requested_items.

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?

Usage is only implied by the parenthetical "custom_fields names to use when placing a request," which hints at the workflow (look up item before calling create_service_request). There is no explicit statement of when to use this tool versus list_service_items or search_service_items, and no prerequisites or failure conditions are named.

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