План на день

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

With no annotations at all, the description carries the full burden, and it does disclose the meaningful behavior: aggregation from the user's cards, the two grouping buckets, the sort keys, and the dual return shape. What it omits is whether the call has any side effects (it appears read-only but never says so) and whether the limit default of 500 can silently truncate a large plan.

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?

A single well-formed sentence that front-loads the action and then enumerates grouping, sorting, and return shape in logical order. No filler or repetition. It is dense but every clause carries information.

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?

There is no output schema, so the description correctly spends its words describing the return value (markdown text plus structured card list), which is the critical missing piece. Six optional parameters are all covered by the schema. Remaining gaps are the lack of side-effect confirmation and the undefined notion of 'priority' ordering.

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 description coverage is 100%, with every one of the six parameters documented in-schema including the role enum and defaults. The description adds nothing about parameters, which is acceptable at this coverage level but means it earns only the baseline. It does not, for example, explain how as_of_date interacts with the 'Overdue'/'Today' buckets.

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 output artifact: builds a day plan from the user's cards, grouped into 'Overdue' and 'Today', sorted by priority and due date, returning markdown plus a structured list. That is much more concrete than a bare 'plan' tool. It stops short of naming sibling tools (kaiten_today_tasks, kaiten_overdue_cards, kaiten_search_cards) that overlap heavily with it, so the agent must infer the distinction.

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 description of what a 'day plan' is, but there is no explicit when-to-use / when-not-to-use statement. Given siblings like kaiten_today_tasks and kaiten_overdue_cards that return overlapping card sets, an explicit 'prefer this over those when you want a combined, formatted view' would have been the highest-value sentence. The agent has to decide between them on its own.

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