complete_task

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

Beyond the annotations, the description discloses the precise state changes (status, percent, timestamp) and the important edge case that completing a repeating task is refused to avoid ending the series. This adds meaningful behavioral context that the annotations do not provide, and nothing contradicts the annotations.

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 tight sentences: the first front-loads the core action and resulting values, and the second handles the crucial repeating-task exception with a clear explanation. There is no filler or redundant restatement of the tool name or schema.

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 mutation tool with strong annotations and fully documented parameters, the description covers the essential effect and the main refusal case. The absence of an output schema is acceptable, though a brief note on what is returned after completion would make it fully complete.

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 input schema already documents all three parameters with 100% coverage, including the conditional-write meaning of etag and the list identifier. The description adds no parameter-specific meaning, but it does not need to since the schema carries the burden.

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 opens with a specific verb and resource ('Mark a task done') and specifies the exact resulting state: status COMPLETED, 100 percent, and current timestamp. It also clearly distinguishes behavior from related tools by stating that repeating tasks are refused, so there is no ambiguity about what this tool does.

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?

It gives clear usage context for ordinary single-occurrence tasks and explicitly excludes repeating tasks with a rationale. It does not name an alternative tool such as update_task or uncomplete_task, but the refusal condition is concrete enough for an agent to decide when not to call it.

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