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

Annotations already declare it as a non-destructive write (readOnlyHint=false, destructiveHint=false). The description adds real context beyond them: 'reaches no one' (no guest notifications), reversibility via block_dates, and the Cotlet API key/auth requirement. It stops short of describing effects on existing bookings within the range.

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?

Front-loaded with the core action, four compact sentences that mostly earn their place. The 'reaches no one and block_dates undoes it, so it runs without asking' clause is slightly convoluted but conveys multiple useful facts economically.

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 4-parameter mutation tool with full schema coverage and annotations, this covers the important agent-facing facts: reversibility, no notification side effects, no confirmation needed, and auth requirements. No output schema exists, but the return format is not addressed, leaving a minor gap.

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 the schema already documents listing_id, from, to, and site_id, including the 'default: all sites' behavior for site_id. The description adds no parameter syntax or nuance beyond 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 and resource ('Open blocked dates again for booking', 'Turns availability back on') and explicitly frames itself as the inverse of block_dates, so an agent can distinguish it from the sibling without opening either schema.

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 references the alternative (block_dates) as the inverse operation and justifies why it runs without confirmation, which is useful context. However, it doesn't state when an agent should reach for this vs. its calendar/availability siblings, so usage is only implied.

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