Query calendar free/busy

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

With no annotations, the description carries full burden, and it does add one meaningful disclosure: the tool returns BUSY intervals from which the agent must derive free windows (not a ready-made list of free slots). However, it omits permissions, rate limits, error behavior, and return shape for what is otherwise an undocumented read.

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?

A single front-loaded sentence with no filler, and the core action is stated first. It is efficient, though arguably under-specified for a tool with no annotations and no output schema.

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?

The purpose is adequately conveyed, but with no annotations and no output schema, the description should carry more behavioral weight than it does. It gestures at return content (busy intervals) but leaves return format, permissions, and calendar-ID defaults 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 description coverage is 100%, so all five parameters (items, account, timeMin/timeMax, timeZone) are already documented in the schema. The description adds only a hint via "across calendars" and nothing about the required timeMin/timeMax or defaults, so the 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?

The description names a specific verb ("Query") and resource ("busy intervals across calendars") and states the goal ("find free meeting windows"). This clearly distinguishes it from siblings like list_events or get_event, though it does not name those siblings explicitly to route the agent.

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?

Usage is only implied: an agent can infer it should call this before scheduling a meeting, but there is no explicit when-to-use, when-not, or reference to alternatives such as google_calendar_list_events for actual event details.

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