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

No annotations are supplied, so the description carries the full behavioral burden. It usefully discloses that apps and logins persist across the resume, but says nothing about whether this is a billable/state-mutating operation, what error occurs if the phone isn't parked, or how long a resume takes.

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 short sentences, front-loaded with the action and followed by the one piece of behavior worth knowing. Nothing is wasted or padded.

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 one-parameter lifecycle tool with a fully described schema and no output schema, the description covers what it does and the key state-preservation behavior. Only minor gaps remain around preconditions and failure modes.

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 the single phone_id parameter is fully documented in the schema, so the baseline of 3 applies. The description adds only a weak constraint that the id should reference a parked phone, with no format or validation detail beyond 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?

The description gives a specific verb and resource ("Resume a parked phone") and implicitly distinguishes itself from the sibling park_phone by naming the state it operates on. It falls short of a 5 only because it never names the sibling or the broader lifecycle 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?

Usage is implied by the precondition "parked phone" — an agent can infer it should call this only on a parked device. There is no explicit statement of alternatives (e.g., create_phone for a fresh device) or of what happens if the phone is not parked.

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