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

Annotations already cover the safety profile (readOnly, idempotent), and the description adds substantive behavior on top: the returned URL is NOT applied to the Pin, and the billing field reports charges plus refund state on failure. That is exactly the kind of context annotations cannot carry.

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?

Four short sentences, front-loaded with purpose, then cadence, then the critical gotcha (not applied yet), then the return fields. Nothing is wasted and the most failure-prone detail is not buried.

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?

Despite output schema being present, the description still flags the two return fields that drive downstream decisions (variationUrl, billing), so an agent knows what to do on success and on failed regeneration. Nothing needed to invoke or interpret it is missing.

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 regenerationId is already documented as 'the id returned by regenerate_pin_design'. The description reinforces that lineage through its usage narrative but adds no format or constraint detail beyond the schema. Baseline 3 is appropriate.

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 — poll the status of a design regeneration — and ties it to the originating tool regenerate_pin_design, which cleanly separates it from get_generation_status, get_copy_generation_status and get_pin_design. An agent can pick this tool without opening the 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?

Gives an explicit polling cadence (~15 seconds, typically completes in a few minutes) and names the required follow-up: pass the returned variationUrl to select_pin_design_variation. The full lifecycle — start, poll, apply — is spelled out rather than left to inference.

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