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

Goes far beyond the destructiveHint/openWorldHint annotations: it says lockedUntil freezes days for everybody including the user until changed, editWindowDays scopes others' edits, null clears, omitted fields persist, rules survive plan lapse, and without confirm the call only previews how many hours get frozen.

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?

Purpose is front-loaded and every clause carries behavioral information about locking, scope, or the preview. The single dense run-on with semicolons is harder to scan than it needs to be.

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?

With no output schema and a destructive mutation, the description supplies everything needed: confirm gating, the preview result, scope of the freeze, clearing semantics, and the Pro-plan constraint.

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 100%, so baseline is 3; the description still adds meaning the schema does not carry, notably that a field left out stays unchanged and that rules keep protecting hours if the plan lapses. It largely restates the null/range semantics already in the schema.

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: sets time rules that close logged hours on all projects the user owns. It explicitly covers what the rules do and is clearly distinct from the read-only sibling get_time_rules.

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?

Explains the confirm-preview requirement and that turning rules off is allowed on every plan, giving clear context for use. It does not name an alternative tool or say when a value should be left out rather than nulled, so it stops short of explicit routing guidance.

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