prune_design_render_cache

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

No annotations exist, so the description carries the full burden. It does disclose the important behavioral fact, that only cached PNGs (not designs or source files) are deleted, and that deletion is age-scoped, but it omits whether the operation is irreversible, whether it requires Pro entitlement (the upsell text hints at gating without clarifying), and what the call returns.

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 of the four sentences are marketing copy about Kiln Pro features, calibration, and an upgrade URL, none of which helps an agent select or invoke a cache-pruning tool. The one useful sentence is correctly front-loaded, but the rest is pure noise that competes for attention.

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 simple one-parameter operation with a fully documented schema and no output schema, the essential fact (what is deleted and the age cutoff) is present. What is missing is irreversibility/entitlement disclosure, and the promotional block actively adds ambiguity rather than filling that gap.

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% and the schema already documents max_age_days with its default of 30. The description restates the parameter as the age threshold, adding no format or boundary detail (minimum, units, behavior at 0), which is the baseline expectation when the schema does the work.

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 first sentence gives a specific verb and resource: remove cached PNGs, with a scope qualifier (older than max_age_days). No sibling in the very large sibling list appears to do the same thing, but the description never names a related tool (e.g. list_cached_models, delete_cached_model) to confirm the distinction, so it stops short of 5.

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?

There is no statement of when to call this, when not to, or what the consequence of omitting max_age_days is, even though the parameter is optional and defaults to 30. The remaining sentences are a pricing upsell rather than guidance, so the agent gets no routing or prerequisite information.

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