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

Annotations declare the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true), so the description need only add context. It does: no watermark, exact App Store pixels, link validity of 7 days, and conditional inclusion of header/search images when the set has a header. It stops short of stating auth/Permission needs or rate limits, keeping it at 4 rather than 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?

Two sentences, front-loaded with the core action and outcome, then the qualifying conditional detail. Every clause (pixels, no watermark, link TTL, image dimensions) earns its place.

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 single-parameter tool with no output schema, the description covers what is produced (download links with 7-day validity) and the exact deliverables (3840x1646 header, 3840x2560 search image). Nothing an agent needs to invoke it correctly 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 description coverage is 100% and the single set_id param is documented as 'set_id returned by design_set.' The description adds no syntax or meaning beyond the schema, so the baseline of 3 applies.

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 outcome ('Render the unlocked set ... and return download links') with the exact resource and pixel fidelity, and the granted/unlocked scope cleanly separates it from design_set, get_set, and unlock_set. An agent immediately knows this is the export step.

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?

The phrase 'the unlocked set' implies the unlock_set prerequisite, which is useful context, but no alternatives (get_set, send_to_app_store) are named and there is no explicit when-to-use or when-not guidance. Usage is only implied.

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