Apply an effect

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

Annotations already declare readOnlyHint=false, and the description confirms this is a mutating operation by saying it adds an effect. It adds useful context about setting parameters in the same call and accepting display names or matchNames, but it does not disclose side effects or failure behavior.

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 front-loaded sentences with no filler. The first states the operation and optional behavior; the second gives identifier formats and examples.

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 mutating tool with five parameters and a nested object, the description plus schema provides enough context to select the tool and invoke it correctly: effect name, layer, comp, and parameters are all covered. Missing return/error behavior is a minor gap but not critical for selection.

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 schema already documents each parameter, provides an example for the parameters object, and explains color format and where to find exact parameter names. The tool description repeats only the display-name/matchName distinction with examples, adding marginal value.

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 action ('Add an effect to a layer') and a clear resource, plus optional parameter setting. This distinguishes it from siblings like ae_remove_effect and ae_set_property, and concrete identifier examples reinforce the purpose.

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 description implies the primary use case: adding an effect and optionally setting parameters in one call. However, it does not explicitly name alternatives or state when not to use this tool, though the schema does point to ae_list_effect_params for parameter-name lookup.

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