add_countdown

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

No annotations are provided, so the description carries the full behavioral burden. It does not say what happens with duplicates, whether `id` is optional or auto-generated, what the tool returns, or any side effects. Only the time-format behavior of `when` is disclosed, which is parameter semantics rather than tool behavior.

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, front-loaded with the tool's purpose followed by the critical format constraint. Nothing is wasted, though the economy comes partly from omitting information rather than from tight editing.

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?

This is a mutation tool with no annotations, no output schema, and 0% schema description coverage across four parameters. The description covers only the `when` format, leaving the ID/color/title parameters, return value, and side effects entirely unspecified.

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 for four undocumented parameters. It compensates well for `when` (local time, no timezone, two accepted formats), but says nothing about `id` (nullable, likely optional), `color`, or `title`, leaving three of four parameters opaque.

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 clear verb+resource ("新建倒计时" / create a new countdown), which maps unambiguously to the add_countdown name. It does not explicitly name the sibling operations (update_countdown, delete_countdown) to draw the boundary, but the create verb is still specific.

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 guidance about when to create a countdown versus when to use update_countdown or list_countdowns, nor are there prerequisites or conditions. The intent is only implied by the tool's name.

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