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

Annotations already declare readOnlyHint=false and openWorldHint=true, but the description adds real value beyond them: confirmation-by-default with an opt-out, the warning that the call reaches other people, and the auth requirement (Cotlet API key with app access). It does not cover reversibility/undo or rate behavior, keeping it from a 5.

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?

Sentences are front-loaded with the action and effect, then prerequisites, then safety/confirmation guidance. It is slightly verbose (five sentences, some overlapping confirmation/scoping content) but each sentence carries distinct information.

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 two-parameter mutation with annotations and no output schema, the description covers precondition, effect on unnamed guests, confirmation posture, and auth. The main remaining gap is what the caller sees after the call (approval result per guest) and how to reverse an approval.

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 event_id and guest_ids are already documented with their source tools. The description adds only the semantic mapping that the named guests are the ones approved; the baseline of 3 applies when the schema does the heavy lifting.

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 (Approve) and resource (pending guests) and scopes it to 'a Guest Approval event', so the agent immediately knows the precondition. It also states the downstream effect (only approved guests have access), which distinguishes it from siblings like check_in_guests or invite_guests.

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 gives the enabling condition ('an event that has Guest Approval on') and the default behavior for guests not named ('stay Pending'), which tells the agent the tool is selective rather than bulk. It doesn't explicitly name a sibling alternative (e.g. check_in_guests) or say when-not to use it, so it falls short of a 5.

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