get_device_last_used

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the 'read-only' remark in the description is largely redundant. What the description does usefully convey is the result semantics — a single device representing the last sync — but it says nothing about what happens when no device has synced or whether the result is scoped to the authenticated user.

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 with the core behavior front-loaded, so an agent can grasp the purpose immediately. The date-format parenthetical earns no place in a call with no date arguments and could be dropped.

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 zero-parameter read with an output schema and safety annotations already in place, the description covers what is needed to select and invoke the tool. The remaining ambiguity (behavior when nothing has synced, which device wins in a multi-device account) is minor but real.

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 tool takes zero parameters, so the baseline is 4 and no parameter explanation is required. The 'Dates are YYYY-MM-DD' parenthetical is irrelevant to a parameterless call and reads as boilerplate noise rather than added meaning.

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 and resource — return the most recently synced device — which is distinguishable from the sibling get_devices (a full device list). It does not explicitly name get_devices as the alternative, so a small differentiation gap remains, but the scope is unambiguous.

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?

There is no explicit when-to-use or when-not-to-use guidance, and the closest alternative (get_devices) is never named. Usage is only implied by the phrase 'synced last', leaving the agent to infer that this is a single-item lookup rather than a listing.

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