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

Annotations only declare write/idempotent/non-destructive. The description adds real behavioral context beyond them: 'off' means timer and reminders only, nothing stored, no plan required, and 'full' is the default. It does not clarify what happens to already-recorded data when switching to 'off', which is the one consequential ambiguity.

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?

One dense sentence with no filler, and the two modes are presented in a clean parallel structure with the default flagged immediately. The compression makes it slightly terse to parse but nothing is wasted.

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 two-parameter toggle with no output schema, the description covers mode semantics and the safety story is carried by annotations. It still omits the date-default behavior and whether prior recorded data is affected by switching to 'off' — a meaningful gap for a 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 50% and the mode enum carries no inline description, so the description does the work by defining both values ('full' = everything recorded, default; 'off' = timer and reminders only). It compensates well for the enum but says nothing about omitting 'date', leaving that parameter's absence behavior unexplained.

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 the resource ('Tracking for a day') and enumerates the two possible states, so an agent can tell this is the switch controlling whether a day's data is recorded, distinct from set_settings or set_routines. It is slightly noun-phrase-led rather than verb-led ('Set...'), but the intent is unambiguous.

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 useful selection context by naming 'full' as the default and explaining what 'off' means, which implicitly tells the agent which value to pick. However, it never states when to call this tool versus siblings like set_settings, nor any prerequisites or exclusions.

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