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

Annotations give destructiveHint=true and idempotentHint=true, but the description goes well beyond them: same calendarEventId is a no-op, same event with a new meetingStart is a RESCHEDULE that only moves the time, and same event on a different person is refused. It also names the destructive side effects (cancelling remaining steps) that justify the destructive hint.

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 action and its effects, then idempotency semantics. Dense but nearly every sentence carries non-obvious information; a little tightening of the long sentences would reach the top mark.

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 an 11-parameter mutation tool with no output schema, the description covers identity resolution, idempotency/reschedule behavior, and side effects. Only minor gaps remain, such as failure modes when the contact cannot be resolved.

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 baseline is 3, but the description adds real meaning: calendarEventId is the idempotency key, meetingStart drives reschedule behavior, campaignId is required when a contact sits in multiple campaigns, and sessionId only applies when the person is in no campaign. These disambiguate when each optional identity field should be passed.

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 precise verb+resource (record a booked call) and enumerates the exact state changes: booking status `booked`, outcome `meeting_booked`, remaining steps cancelled, `bookedAt` stamped. This clearly separates it from siblings like li_mark_outcome, li_mark_stopped, li_cancel_steps and li_mark_booking_cancelled.

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?

"Valid from any status — someone may book straight off a sequence link without ever replying" tells the agent the trigger condition well. It also offers routes to identify the person (profileUrl from li_match_contacts, or contactId). It does not explicitly name when to prefer a sibling (e.g. li_track_booking or li_mark_booking_cancelled), so it stops short of the top mark.

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