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

Adds rich behavior beyond the annotations: code and discount are immutable after creation (a wrong code requires deleting and recreating), expiry only blocks new redemptions while leaving already-applied discounts intact, the change affects what members pay, calls are confirmed by default (switchable), and it requires a Cotlet API key with app access. This is exactly the context annotations (readOnlyHint=false, destructiveHint=false, openWorldHint=true) do not convey.

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?

Purpose is front-loaded, but the body is a string of clipped fragments and repeats the confirmation point three times ('it asks first', 'you confirm each call', 'confirm with the user before each call'). Some trimming would sharpen it without losing 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 9-parameter creation tool with no output schema, the definition covers immutability, expiry semantics, confirmation defaults and auth prerequisites. Only minor gaps remain (e.g., interaction between offer_ids and applies_to), and the annotations already carry the safety profile.

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 every parameter is already documented with enums and defaults. The description's mention of 'a discount, target, limits and expiry' loosely maps to value/discount_type, applies_to, redemption_limit and expires_on but adds no syntax or format detail beyond the schema. Baseline 3 is correct 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 and resource (creates a coupon) plus scope (discount, target, limits, expiry) and even the product location (Marketing > Coupons). An agent can distinguish it from sibling creates like uscreen_create_collection or uscreen_create_live_event without opening any 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?

Usage is only implied by the domain (create a coupon). There is no explicit when-to-use vs when-not-to-use and no alternative tool named, even though related coupon operations exist. The confirmation guidance is behavioral rather than selection guidance.

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