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

Annotations already mark it as read-only, idempotent, and non-destructive, so the bar for extra disclosure is lower. The description adds meaningful behavioral context by specifying the return payload, what counts as a conflict, and the account prerequisite/default resolution behavior. This goes beyond simply restating 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?

The description is compact and front-loaded: purpose first, return shape second, prerequisites and defaults third. Every sentence carries useful information with no redundant filler or restatement of the tool name.

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?

Even without an output schema, the description fully explains the return value, including the shape of conflictingEvents. It also covers the prerequisite account connection and the default fallback behavior. This is sufficient for an agent to know what the tool does, what it returns, and what inputs matter.

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?

The input schema has 100% parameter coverage, so the baseline is 3. The description adds value by explicitly documenting the behavior of googleAccountId when omitted and framing startTime/endTime as the requested range to check. This is helpful beyond the raw schema descriptions.

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 states a specific action — checking whether a time slot is available — with a clear resource (Google Calendar) and a defined result shape ({ available, conflictingEvents }). It distinguishes itself from sibling tools like get_free_slots by emphasizing a specific time slot rather than general free-slot discovery.

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 establishes when to use it: to check a specific time range for conflicts. It also provides the critical prerequisite that a Google account must be connected and linked to the workspace, plus the default behavior when googleAccountId is omitted. It does not explicitly contrast with related alternatives like get_free_slots, though the context is strong enough.

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