Set fade-in and fade-out durations in seconds for every selected media item in REAPER. Pass -1 for either value to leave it unchanged.
Set fade-in and fade-out (seconds) on every selected media item. Pass -1 for either to leave it unchanged.
| Name | Required | Description | Default |
|---|---|---|---|
| fade_in_sec | No | ||
| fade_out_sec | No |
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It discloses batch scope and the -1 sentinel, but says nothing about what happens with no selection, whether fade values are clamped to item length, whether the operation is undoable, or how errors surface.
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 short sentences with zero filler; the operation is front-loaded and the sentinel rule follows as essential clarification. Every sentence 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 simple two-parameter setter with no output schema and no annotations, the description covers scope, units, and the sentinel default. It omits edge-case behavior (empty selection, value clamping), which is a minor gap given the tool's low complexity.
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 0%, so the description must compensate, and it largely does: it gives units (seconds) for both parameters and, critically, explains the -1 sentinel that the schema only shows as a bare default. This is close to full parameter meaning, though it does not state valid ranges.
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), specific resource (fade-in and fade-out seconds), and precise scope (every selected media item). No sibling tool performs fade operations, so no differentiation is needed, and an agent can immediately tell what this does.
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 'on every selected media item' implies the prerequisite that items must be selected first, but there is no explicit when-to-use, when-not-to-use, or alternative guidance. Usage is inferable rather than stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.