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

Annotations already declare the mutation/safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false). The description adds genuinely non-obvious context beyond that: it counts against the plan's discount-profile cap, requires host permission, and requires event_id + tiers. It stops short of describing return/rollback behavior, so 4 is fitting.

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-loads the core action and definition, then ordering alternatives, quota impact, and requirements. Dense but every clause contributes; the em-dash definition and cap emphasis are efficient. Slightly heavy, hence 4 rather than 5.

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 mutation tool whose annotations cover safety and with no output schema, the description is nearly complete: requirements, dependency alternative, quota, permission, and tier structure are all present. Missing only minor details like profile_name semantics and scheduling behavior.

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?

With 0% schema description coverage, the description carries the burden and delivers: it marks event_id + tiers required, clarifies tier keys are ticket_class_ids (which schema propertyNames does not), and notes percent/fixed plus optional max_uses and schedule. It omits profile_name and the starts_at/expires_at split, so not a perfect 5.

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 (Create) and resource (reusable discount PROFILE), and clarifies the conceptual distinction from sibling create_promo_code by explaining it is a shared config that many codes attach to. An agent can distinguish it from create_promo_code without opening either schema.

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?

Explicitly names the alternative and the selecting condition: 'For a single coupon or discount code, use create_promo_code instead.' It also states the context (on a live event, must be a host) and the plan-cap consequence, leaving little to inference.

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