proofcut

Overview Schema Source Related Servers Discussions Admin

canvas

DestructiveIdempotent

Read or change the project's canvas shape, which controls every frame size and render output. Set a custom widthxheight, reset to the footage-derived shape, or preview the effect before applying it.

Instructions

Read or change the shape this project renders at.

The canvas is project state and every frame size derives from it — the MLT profile and the captions' reference canvas both read it, so a project cannot quote caption sizes against one shape and render another. Call it with no size to read what is in force plus the footage-derived shape it would fall back to; reset drops the override and returns to that shape.

size is "WIDTHxHEIGHT", e.g. "1080x1920" for a vertical reel. Both edges must be even.

Setting one has a routing consequence, reported as routes_through: an overridden project renders through the MLT writer whatever its source count, because auto-editor cannot be handed a canvas it will honour. An override that changes the aspect crops to fill rather than pillarboxing, so cropped names every clip that loses footage to it — use reframe to see or change which part of each one is kept.

Input Schema

TableJSON Schema

Name	Required	Description
`path`	No	The project directory to act on. Omit it — the usual case — when this server is bound to a project (started as `proofcut -C DIR mcp`, or inside a project; `ping` says which): it then resolves to that one bound project, a relative path resolves against it, and a path outside it is refused by name. Unbound, `path` is the whole address and omitting it refuses rather than guessing.
`plan`	No	Resolve the whole call and report what it would do, writing nothing. Prefer it over doing the thing and undoing it.
`size`	No	`WIDTHxHEIGHT`, e.g. `1080x1920` for a vertical reel. Both edges must be even. Omit it to read what is in force plus the footage-derived shape it would fall back to.
`reset`	No	Drop the override and return to the footage-derived shape.

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed13 schema fields changedv0.25.0Sep 16, 2026

removedInput schema / properties / path / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

addedInput schema / properties / path / description

Added value: +"The project directory to act on. Omit it — the usual case — when this server is bound to a project (started as `proofcut -C DIR mcp`, or inside a project; `ping` says which): it then resolves to that one bound project, a relative path resolves against it, and a path outside it is refused by name. Unbound, `path` is the whole address and omitting it refuses rather than guessing."

removedInput schema / properties / path / title
```
Removed value: -"Path"
```

addedInput schema / properties / path / type

Added value: +[
+  "string",
+  "null"
+]

addedInput schema / properties / plan / description

Added value: +"Resolve the whole call and report what it would do, writing nothing. Prefer it over doing the thing and undoing it."

removedInput schema / properties / plan / title
```
Removed value: -"Plan"
```

addedInput schema / properties / reset / description

Added value: +"Drop the override and return to the footage-derived shape."

removedInput schema / properties / reset / title
```
Removed value: -"Reset"
```

removedInput schema / properties / size / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

addedInput schema / properties / size / description

Added value: +"`WIDTHxHEIGHT`, e.g. `1080x1920` for a vertical reel. Both edges must be even. Omit it to read what is in force plus the footage-derived shape it would fall back to."

removedInput schema / properties / size / title
```
Removed value: -"Size"
```

addedInput schema / properties / size / type

Added value: +[
+  "string",
+  "null"
+]

removedInput schema / title
```
Removed value: -"canvasArguments"
```

First observedv0.24.0Sep 15, 2026

TDQS

A4.9/5.0

Behavior5/5

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

Annotations flag `destructiveHint` and `idempotentHint`; the description goes beyond by detailing the routing consequence (override forces MLT writer), the cropping behavior (aspect change crops to fill, not pillarbox), and the side‑effect on caption quoting. It even mentions the `plan` flag as a safer alternative, which is exactly the kind of operational detail an agent needs. No contradiction with 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 moderately long but every sentence is packed with unique, actionable information. It is front‑loaded with the core purpose, then flows naturally into call patterns, behavioral consequences, and parameter details. There is no fluff or redundancy.

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 state‑changing tool with subtle rendering implications, the description covers everything: what it does, when to call it, what happens on override (routing, cropping), how to preview safely, and which sibling to use for fine‑grained adjustments. The presence of an output schema and rich parameter descriptions further reduces any missing context. Nothing essential is left out.

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?

The input schema already covers all four parameters with detailed descriptions (100% coverage). The main description adds extra meaning for `size` (even edges, vertical example) and `reset` (drops override), and explains the consequences of setting a size (routing, cropping). This goes beyond the schema, so a 4 is warranted; it stops short of a 5 because the schema already does much of the heavy lifting.

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 opens with a specific verb-resource pairing ('Read or change the shape this project renders at') and goes on to explain exactly what the canvas is, how it relates to project state and rendering, and why it matters (caption quoting consistency). It also names a related tool (reframe) for a specific sub‑task, which distinguishes it from siblings without needing to list them.

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?

The description gives explicit call patterns: reading with no `size`, resetting with `reset`, and using `plan` to preview. It also tells the agent when to delegate to `reframe` for changing which part of a crop is kept, effectively stating when not to use this tool. This is model guidance.

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

Deploy Server