checkin

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

With no annotations provided, the description carries the full behavioral burden. It discloses the daily limit and the server's response to repeated calls, which are the key non-obvious behaviors. It could also mention authentication requirements, but the core behavioral traits are covered.

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 deliver the essential information with no filler. The action is front-loaded, and the behavioral constraint follows immediately. Every word earns its place.

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 tool with no output schema, the description covers the essential facts: what it does, how often, and what happens if called again. It is slightly incomplete in that it does not mention authentication or the shape of the success response, but this is minor for such a simple action.

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 has zero parameters, and the schema coverage is 100% trivially. The description adds meaning about the action's purpose without needing to explain parameters, so the baseline 4 is appropriate.

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 states a specific verb ('Perform') and a clear resource ('the daily check-in') with a concrete outcome ('collect energy points'). It is unambiguous and distinct from all sibling tools, none of which perform a daily check-in.

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 explicitly tells the agent this action can be performed once per day and that repeated calls will return an 'already checked in' result. This is clear usage context, though it does not discuss alternatives because none are relevant.

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