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

Annotations already handle the read-only, non-destructive, and closed-world behavior, so the burden on the description is lower. The description adds a minor behavioral detail about where the ID comes from, but it offers no extra visibility into errors, permissions, or response shape. The output schema covers the rest, making this acceptable.

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?

One sentence containing only essential information: the verb, resource, and parameter source. No filler, no repeated schema, and the content is front-loaded and scannable.

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 a simple get-by-ID with an output schema, one documented parameter, and read-only annotations. The description plus structured fields cover what an agent needs to choose and invoke it correctly.

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 0%, so the description must compensate for the caseId parameter. It helps by stating that caseId is an ID from list_cases, providing source and semantic value beyond its simple string type. This works well for a single required parameter.

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?

Uses a precise verb and resource: 'Get one case by an ID returned by list_cases.' It clearly distinguishes this from list_cases (single vs. many) and from create_case/update_case/delete_case. An agent can immediately understand the tool's function.

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 by linking to list_cases as the source of the required ID, so an agent understands when this tool makes sense. It doesn't explicitly state what not to use, but the purpose of the single-case retrieval is well implied by the sibling list_cases tool.

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