ae_setBlendingMode

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

The annotations already declare this is a non-read-only, non-destructive, closed-world write, so the safety profile is covered. The description usefully signals that any valid AE mode name is accepted and lists canonical examples, but says nothing about behavior on an invalid mode string, whether the change is undoable, or what happens if the layer isn't found — gaps that matter for a mutation tool.

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?

One sentence, front-loaded with the verb and resource, with the value list placed where it aids invocation. Nothing extraneous.

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 three-parameter, single-property mutation with annotations and no output schema, the description covers the essential facts: what it does and what values are accepted. Only error/edge-case behavior is missing, which is a minor residual gap given the structured fields already carry the rest.

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 67% and, critically, the required `mode` parameter has no enum in the schema; the description compensates by enumerating concrete valid values (normal, add, screen, multiply, ...) which the schema does not provide. The `layer` and `compositionName` params are already documented in-schema, so the description doesn't need to repeat them.

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 description uses a precise verb ('set') and a specific resource ('layer blending mode'), scoped to After Effects, which separates it from the sibling switch/transform tools (ae_setLayerSwitches, ae_setTransform). It never explicitly names alternatives, so it stays at 4 rather than 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?

The usage is only implied — an agent can infer this is the tool for changing a layer's blend mode, but the description gives no when-to-use versus when-not guidance, no prerequisites (e.g. an open comp, a selected/targeted layer), and no note about which sibling to use for other layer properties.

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