close_period

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

With no annotations, the description carries the full behavioral burden and does so: precondition (no todo/in_progress tasks), side effects (stores result_markdown as the period's result, marks the milestone done), and re-invocation semantics ('rewrites the retrospective and changes nothing else'). Idempotency and mutation scope are both disclosed, which is unusual and valuable.

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?

Front-loaded with the trigger, then precondition, then effects, then re-call behavior — the ordering is sensible. The first and second paragraphs restate the same 'quarter's work is over' idea, a small redundancy that could be merged.

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?

No output schema and no annotations, so the description has to be self-sufficient, and it nearly is: preconditions, side effects, and idempotency are all present. It leaves the `key` argument and any indication of what the call returns undefined, which an agent may need for an unfamiliar mutation tool.

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 0%, so the description must compensate. It explains period's YYYYQn format, and constrains result_markdown's language, length (~30 lines), and content (summary vs goal, lessons, carried-over task old id -> new id), including where it is stored. The `key` parameter is left entirely undefined, which keeps it from a 5.

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 plus the key artifact it produces: 'Close a period (YYYYQn) and record its retrospective.' The period-key format and retrospective recording make it unmistakably distinct from sibling open_period and from get_retrospective.

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?

Gives a clear triggering condition ('when a quarter's work is over and the user wants it closed with a retrospective') and an explicit refusal condition ('refuses while any task is still todo or in_progress'). It never names open_period as the counterpart to use when the period isn't ready to close, so the routing back to alternatives is only implied.

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