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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false; the description reinforces idempotency concretely ('no effect') and discloses the state transition and downstream consequence (device can receive forms). It stops short of noting permissions or what the response contains, but on top of annotations this is solid.

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?

Three short sentences, leading with a 'WRITE:' marker and the core action, then the edge case, then the endpoint. Nothing is wasted.

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 single-parameter mutation with full annotation coverage, the definition supplies precondition, effect and idempotency. Only the return payload is unspecified, a minor gap given there is no output schema.

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?

Only one parameter, documented in the schema at 100% coverage including a cross-reference to list_devices' `id` field. The description adds nothing beyond the schema, which is the baseline expectation here.

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 ('approves') and resource ('a device'), plus the exact precondition (pending_approval is true) and the outcome ('so it can receive forms'). This is unambiguously distinct from read siblings like get_device and list_devices.

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?

Makes the trigger condition explicit ('a device that is waiting for approval') and covers the degenerate case ('approving an approved device has no effect'). It doesn't name an alternative tool for devices not in pending state, but the condition is clear enough to route correctly.

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