get_user

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

Annotations already declare readOnlyHint: true, so the read-only nature is known. The description adds minimal extra behavioral context—only 'full details,' which implies a comprehensive response. It does not disclose error behavior, field selection, or relationship to other resources, but with the annotation covering safety, the added value is modest.

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 concise sentence, front-loaded with the verb and resource, and no filler. It communicates the essential information in under 10 words.

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 get-by-ID tool with one parameter and no output schema, the description is adequate. It states the action and scope. It doesn't list returned fields, but 'full details' implies completeness. The readOnlyHint is already provided by annotations. No critical missing information for invoking the tool 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 clarify the userId parameter. The phrase 'by ID' directly explains that userId is the unique identifier, which adds meaning beyond the bare schema (type: number). This is sufficient for a single-parameter tool, though it could be more explicit about what kind of ID (e.g., user ID in the system).

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 states a specific verb ('Get'), a resource ('full details for a single user'), and the key discriminator ('by ID'). This clearly distinguishes it from the plural sibling get_users, and matches the singular get_invoice/get_customer pattern in the sibling list.

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 gives clear context: use this when you need full details for a single user identified by ID. It does not explicitly mention alternatives or when not to use it, but the distinction from get_users (plural) is implicit and obvious. Absence of exclusions is a minor gap.

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