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

Annotations already establish idempotence and non-destructiveness, so the bar is lower. The description adds valuable behavioral context by stating that the operation does not change the score, which is a meaningful side-effect guarantee beyond the annotations.

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, purposeful sentences with no fluff. The main action is stated first, and the important caveat about score preservation is added in the second sentence.

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 simple two-parameter tool with complete schema coverage and informative annotations, the description covers the essential behavioral details: what is being set, the precondition, and a key non-effect. An agent has enough information to decide whether and how to call this 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 description coverage is 100%, so the schema already fully documents both visitId and dates. The description adds no new parameter-level meaning, but it does not need to because the schema carries the weight.

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 uses a specific verb ('set') and resource ('travel dates on something already marked as visited'), making the tool's purpose immediately clear. The phrase 'already marked as visited' differentiates it from creation/add tools, and 'Does not change score' removes ambiguity about side effects.

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 description clearly communicates the context in which the tool is appropriate: the target must already be marked as visited. It does not explicitly name alternatives or when-not-to-use conditions, but the precondition is strong enough to guide an agent toward correct invocation.

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