set_availability_rules

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

Annotations provide idempotentHint=true. The description adds that rules are automatically applied to availability queries (busy-block expansion, masking), and that it overwrites existing rules. No contradictions.

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 concise sentences front-load the purpose and components, then explain behavior. No unnecessary words, efficient structure.

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?

Covers main purpose, effects, and upsert behavior. Could mention default handling (null working_hours removes constraints) but schema describes defaults. Generally complete for a configuration 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 coverage is 100%, so parameters are well-documented. The description summarizes the types (buffer times, working hours) but does not add significant detail beyond the schema. Baseline 3 is appropriate.

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 clearly states the tool's purpose: 'Set or replace the availability rules on a calendar.' It specifies the components (buffer times, per-day working hours) and distinguishes from siblings like 'clear_availability_rules' by noting it overwrites existing 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?

The description implies when to use (to configure availability rules) and notes the effect on queries. It does not explicitly list alternatives but hints at 'clear_availability_rules' for removal. The upsert behavior is explained.

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