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

Annotations already declare the safety profile (destructive, idempotent, open-world, non-read-only), so the bar is lower. The description does add real context beyond them: activation creates a recurring job that can publish to connected channels and is bounded by credit caps, and it only applies to enhanced source images. It stops short of explaining what the destructive/idempotent hints mean in practice, e.g. what credits are consumed or whether activation is reversible.

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?

Three dense sentences with no filler, and the core action leads. Some phrasing is telegraphic ('Only enhanced source images'), which slightly hurts readability but not length.

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?

Output schema exists, so return values need no explanation, and the description covers purpose plus two preconditions. The gap is the four undocumented required parameters and what activation actually changes in the account (recurrence cadence, channel publishing scope), which an agent needs before calling a destructive, non-read-only tool.

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?

All four parameters (brandId, automationId, revision, idempotencyKey) are required with 0% schema description coverage, so the description carries the full burden. It alludes to a 'saved recipe' and matching automation type, loosely implying automationId, but says nothing about brandId, the revision/optimistic-concurrency field, or how idempotencyKey behaves on retry.

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 and resource ('Activate recurring generation'), which distinguishes it from pause_/resume_ siblings, and 'the saved automation type must match this tool' implicitly routes it against the ~20 other activate_* variants. However, it never names image enhancement explicitly as the automation family in the prose, relying on the tool name for that differentiation.

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?

Preconditions are stated ('the saved automation type must match this tool', and that delivery must have been previously approved), which implies when activation is appropriate. But there is no explicit contrast with resume_image_enhancer_automation, pause_automation, or prepare_image_enhancer_automation, so the agent must infer the lifecycle position on its own.

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