MorphaReels

Set clip speed

set_clip_speed

Destructive

Play a clip slower or faster at a CONSTANT rate — the normal way to retime a clip. 1 = source speed, 0.5 = half speed, 2 = double speed; range [0.1, 8]. The trim is unchanged, so the clip's length on the timeline changes to suit: at 0.5x it occupies twice as many frames, at 2x half as many. Audio is time-stretched with pitch preserved. Use add_speed_keyframe instead only when the rate must CHANGE over the clip (a ramp).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "elementId": "<elementId>",
      "speed": "<speed>",
      "projectId": "<projectId>"
    },
    "name": "set_clip_speed"
  }
}

Input Schema

Name	Required	Description
`speed`	Yes	Constant playback rate (1 = source speed, 0.5 = half, 2 = double), in [0.1, 8].
`elementId`	Yes	video.<id>.
`projectId`	Yes	Opaque project id (a v4 UUID, from list_projects/create_project). Selects which existing project this call mutates.

Output Schema

Name	Required	Description
`ok`	Yes	Whether the call succeeded.
`data`	No	The payload, shaped by the tool.
`note`	No	What to do next when not ready.
`error`	No	Why it failed.
`status`	No	For cache-backed readers: whether the answer was ready.
`editorUrl`	No	Opens this project in the editor.

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedSep 17, 2026

removedInput schema / properties / anonymousToken

Removed value: -{
-  "description": "The token create_anonymous_account returned. This connection has no Morpha key, so every call carries it.",
-  "type": "string"
-}

changedInput schema / required

Previous value: -[
-  "elementId",
-  "speed",
-  "projectId",
-  "anonymousToken"
-]New value: +[
+  "elementId",
+  "speed",
+  "projectId"
+]

Changed1 schema field changedSep 15, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "description": "The result envelope every Morpha tool returns.",
+  "properties": {
+    "data": {
+      "description": "The payload, shaped by the tool.",
+      "type": [
+        "object",
+        "array",
+        "string",
+        "number",
+        "boolean",
+        "null"
+      ]
+    },
+    "editorUrl": {
+      "description": "Opens this project in the editor.",
+      "type": "string"
+    },
+    "error": {
+      "description": "Why it failed.",
+      "type": "string"
+    },
+    "note": {
+      "description": "What to do next when not ready.",
+      "type": "string"
+    },
+    "ok": {
+      "description": "Whether the call succeeded.",
+      "type": "boolean"
+    },
+    "status": {
+      "description": "For cache-backed readers: whether the answer was ready.",
+      "enum": [
+        "ready",
+        "not-ready"
+      ],
+      "type": "string"
+    }
+  },
+  "required": [
+    "ok"
+  ],
+  "type": "object"
+}

Changed2 schema fields changedSep 11, 2026

addedInput schema / properties / anonymousToken

Added value: +{
+  "description": "The token create_anonymous_account returned. This connection has no Morpha key, so every call carries it.",
+  "type": "string"
+}

changedInput schema / required

Previous value: -[
-  "elementId",
-  "speed",
-  "projectId"
-]New value: +[
+  "elementId",
+  "speed",
+  "projectId",
+  "anonymousToken"
+]

First observedSep 7, 2026

TDQS

A4.9/5.0

Behavior5/5

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

Beyond the destructiveHint annotation, the description discloses the trim remains unchanged, how timeline length changes (twice/half frames), and that audio is time-stretched with pitch preserved. These are meaningful side effects that the agent needs to know, adding value beyond structured annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three sentences, front-loads the core behavior and range, then adds behavioral consequences and a usage pointer. No filler; every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a constant-rate retime operation, the description covers the effect on trim, timeline length, audio, and the range. It names the sibling alternative. With an output schema present and annotations providing the destructive flag, nothing an agent needs to invoke this tool correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3. The description adds interpretive meaning for the speed parameter (explaining its effect on timeline length and audio) beyond the schema's simple range note. It does not add extra context for elementId or projectId, but those are already well described. Thus a 4 is warranted.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific action ('Play a clip slower or faster at a CONSTANT rate') and identifies the resource ('a clip') and the mode ('the normal way to retime a clip'). It clearly distinguishes from add_speed_keyframe by name, making the purpose unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly provides when-to-use ('the normal way to retime a clip') and when-not-to ('Use add_speed_keyframe instead only when the rate must CHANGE over the clip'), naming the alternative and the exact condition. This leaves no inference required.

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

All MorphaReels tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?