set_gameplay_effect_period

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

Annotations declare destructiveHint=true and idempotentHint=true, but the description goes well beyond them: it discloses that the asset is saved without recompiling and without an undo entry, that execute_on_application is always written (omitting it forces false), and that invalid targets fail before any edit. These are meaningful mutation side effects the annotations alone don't 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?

Front-loads the core action and packs preconditions, side effects, sibling routing, and a return summary efficiently. Slightly dense and includes a minor restatement of the schema's period semantics, but every sentence carries 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?

No output schema exists, and the description compensates with a Returns block listing the returned fields. Combined with preconditions, side-effect disclosure, and sibling guidance, an agent has everything needed to call this mutation tool correctly.

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 the baseline is 3, but the description adds a real nuance beyond the schema: execute_on_application is always written, meaning an omitted value actively sets false rather than leaving it untouched. The period semantics (0 = not periodic) largely restate the schema description, so the gain is modest.

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 (Set) plus the exact properties touched (Period and bExecutePeriodicEffectOnApplication) on the class default object of a GE Blueprint. It names the sibling tools set_gameplay_effect_duration and set_gameplay_effect_stacking, so an agent can distinguish it from adjacent GE-editing tools without opening a 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 explicit preconditions that double as when-not-to-use rules ('A non-GE Blueprint, a running PIE session or a read-only root fails before any edit') and routes the agent to alternatives for related needs (duration for DOT/HOT, stacking for stacks). Nothing about selection is left to inference.

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