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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so 'Read-only' merely restates structured data. 'Counts only' does earn its place by telling the agent no per-entry detail is returned, which prevents follow-up requests for entry-level data. Nothing is said about zero-count days or timezone handling.

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?

Three short sentences, front-loaded with what is returned and terminated by the scope limit. Slight waste in repeating 'Read-only' from the annotations, but nothing is buried or padded.

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 single-parameter read tool with no output schema, the description does sketch the return shape (per-day planned and completed counts). It still omits how days are keyed or labeled and what happens on days with no entries, which an agent needs to interpret results without guessing.

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?

One parameter with 0% schema description coverage, so the schema only contributes a regex pattern, not meaning. The description partially compensates by framing `from` as the start of a seven-day window, but it does not say whether the window is inclusive, whether the date is interpreted in local or UTC time, or what format is expected.

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: counts of planned and completed entries, one per day across a seven-day window starting at `from`. This is concrete enough to distinguish the shape of the output, though it never contrasts itself with the sibling `zarok_get_period_stats`, which plausibly overlaps in intent.

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?

No guidance on when to pick this over `zarok_get_period_stats` or any other read tool in the sibling list. The agent is left to infer that a fixed seven-day window is the selection criterion, which is a meaningful but unstated distinction.

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