Get User

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

The annotations already declare readOnlyHint=true and openWorldHint=true, clearly marking this as a safe read operation. The description adds little behavioral context—no details about error handling (e.g., 404 if user not found), rate limits, or the breadth of 'details' returned. It neither adds significant value beyond annotations nor does it contradict them.

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?

The description is a single, 8-word sentence that leads with the action verb, is immediately scannable, and contains zero unnecessary words. It could not be more efficient.

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?

Given the extreme simplicity of the tool—one parameter, no output schema—the description provides sufficient context for a proficient agent. The openWorldHint suggests it's safe to use in most contexts. A slightly more explicit mention of what 'details' includes (e.g., profile fields, avatars) would push it higher, but this is a minor gap.

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?

The parameter user_id is fully documented in the schema with type and description, giving 100% schema coverage. The description's 'by ID' simply restates the parameter's purpose without adding new semantics. With full schema coverage, the baseline of 3 is appropriate; no additional explanation or usage examples are offered.

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?

Clear subject-verb-object: 'Get details for a single user by ID.' The verb 'Get' plus the unambiguous resource 'user' and the scoping 'by ID' make the purpose immediately obvious. It clearly differentiates from siblings like search_users (which searches) and get_profile (which retrieves the current user).

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 implies usage when a user ID is known and details are needed, but it offers no explicit when-to-use guidance or mention of alternatives such as search_users or get_profile. Unlike the high-scoring get_calls example, no alternative is named, so an agent must infer the appropriate context on its own.

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