Pre-assign devices to a user

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

Annotations already declare readOnly=false, idempotent=true, destructive=false, openWorld=true, so the safety profile is covered. The description usefully explains the deferred effect (linking happens at enrollment, not now), but it does not say what happens when an identifier is already bound to another user, nor whether pre-assignments expire or can be overwritten.

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?

Two sentences, no filler: the mechanism and outcome come first, the operational timing rule second. Nothing is repeated and nothing is buried.

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 two-parameter tool with full schema coverage, rich annotations, and no output schema, the description covers purpose, effect, and timing adequately. The only real gap is conflict/duplicate handling, which matters for an idempotent pre-assignment operation but is a modest omission.

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% and both parameters are documented, so the baseline is 3. The description adds only a light gloss on identifiers ('serial numbers, IMEIs, etc.'), which largely duplicates the schema's own wording; the 100-item cap and email semantics are left to the schema.

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 ('Pre-assign') and resource ('device identifiers') plus the downstream effect: devices are linked to the user automatically upon enrollment. That effect clause distinguishes it well from the read-side sibling get_user_device_identifiers and the inverse remove_device_identifier_from_user, though neither sibling is named explicitly.

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?

Gives a concrete timing rule: 'Use this before powering on a new device,' which tells the agent the precondition for calling it. It stops short of exclusions, e.g. what to do if the identifier is already assigned or whether to prefer this over updating an existing enrollment.

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