List, get, or set automation points for REAPER track parameters like volume, pan, and mute. Setting replaces all existing points with the provided values.
Track envelopes. action: list | get | set. name is REAPER envelope name (Volume, Pan, Mute, ...). set replaces all points. value is native envelope value (Volume 1.0 = 0 dB).
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | ||
| action | Yes | ||
| points | No | ||
| track_index | Yes | ||
| envelope_index | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden; it does disclose the key mutation trait that 'set replaces all points' and clarifies the native value scale. However, it does not say whether list/get have side effects, what set does if points are omitted, or what the response/return behavior is.
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?
Several short fragments pack the action enum, name semantics, set semantics, and value scale without padding. The structure is slightly choppy ('Track envelopes' as an opener) but still front-loads the core operations and keeps the description scannable.
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 5-parameter tool with no output schema and no annotations, this is incomplete: an agent cannot tell what list/get return, how envelope_index is obtained, or how track_index is interpreted beyond its name. The useful fragments are not enough to confidently call all three actions 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?
The schema has 0% description coverage, and the description compensates with useful meanings: name examples (Volume, Pan, Mute), native value scale (1.0 = 0 dB), and set's full-replacement effect on points. But it leaves required track_index and envelope_index semantics unstated, and the inner point fields (beats, shape, tension, selected) are only named in the schema.
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 names the resource (REAPER envelopes) and specifies the operations (list, get, set), so an agent can see this is an envelope-management tool. It is not as crisp as a one-line 'Manage REAPER envelope automation points' and doesn't explicitly contrast with sibling tools, but the action enum makes the purpose clear.
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 guidance on when to choose envelope vs sibling tools (track, item, action, project) or when to use list vs get vs set. The only conditional hint is 'set replaces all points,' which is a behavior, not a usage rule. An agent must infer usage from parameter names.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.