Get item

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

The description says 'Fetches' which aligns with readOnlyHint=true. Annotations already cover the read-only, non-destructive behavior. The description adds no new behavioral detail like error cases or side effects. Since annotations are present, a 3 is appropriate.

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 short sentence that clearly states the operation. Extremely concise and front-loaded.

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 get-by-id operation, this is minimal. It doesn't explain what an 'item' is, whether the operation is idempotent (though read-only implies), or what the return value looks like. Given no output schema, the description should give more context, like 'Returns the full item object'. It's too terse to fully guide an agent.

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% for the single parameter itemId, and the schema already describes it as a path parameter. The description adds nothing about the parameter's meaning or expected format. Baseline 3 is correct.

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?

Description states a specific verb ('Fetches') and resource ('one item'), which clearly indicates a single-resource retrieval. It distinguishes from list operations by specifying 'one', but doesn't name the resource type beyond the generic 'item'.

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?

No guidance on when to use this tool versus alternatives. It doesn't mention that you need an item ID, or that you should use list_items first to get IDs. There's no reference to sibling tools or conditions for use.

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