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

Annotations already declare destructiveHint=true and idempotentHint=true, so the agent knows this mutates state and is safe to retry. The description adds only that the target is a 'previously declared' status of one of three types; it says nothing about permissions, error behavior on a non-existent day, or reversibility beyond what annotations already cover.

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 with the mutation front-loaded and the inference rule clearly separated; no filler. Slightly verbose in enumerating the three status types, but nothing 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?

An output schema exists so return values need no prose, the single parameter is fully documented in the schema, and annotations cover the destructive/idempotent profile. For a one-parameter undo tool, this is nearly complete; only edge behavior on missing entries is unaddressed.

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% and the single parameter's description already includes 'Format: YYYY-MM-DD. Default: today.' The description's 'default to today' and inference instruction duplicate rather than extend the schema, so baseline 3 applies.

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 (Remove/cancel) and a precise resource (previously declared Rest Day, Sick Day, or Travel Day status), which is clearer than the tool name alone and distinguishes it from log_rest_day/list_rest_days. It does not, however, explicitly name the sibling it complements.

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?

The phrase 'previously declared' implies this is for undoing an existing marking, and the INFER block gives concrete invocation guidance for the date. There is no explicit when-not-to-use or named alternative (e.g., log_rest_day to re-mark), so the guidance remains implied rather than stated.

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