FableCut

fablecut_versions

Instructions

A project's version history: saved copies you can go back to, never destructive. Actions: list (default) · save {name?, note?, final?} — keep the project as it is now (do this before big or risky edits, and when the user is happy with a cut) · diff {version, to?} — what changed from that version to now (or to another version): clips added / removed / changed, length, media, settings · restore {version} — put that version back; the current state is saved as a version first, so a restore can itself be undone · update {version, name?, note?, final?} — rename, annotate, or mark the one final cut · delete {version}. project defaults to the open one (fablecut_projects lists ids). Versions are also made on their own: every 10 minutes while the project changes, and before an agent's first edit of a session or a fablecut_set_project rewrite. Restoring changes what the user sees: only when they asked.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "fablecut_versions"
  }
}

Input Schema

Name	Required	Description
`to`	No	diff: compare to this version instead of the current project
`name`	No	save / update: the version's name (default "Version NN")
`note`	No	save / update: what this version is ("client cut, shorter intro")
`final`	No	save / update: mark it the final cut (one per project)
`action`	No	What to do (default list)
`project`	No	The project (p_…); default the open one
`version`	No	The version: its number (3) or "v3"

Schema Changelog

Changes observed during successful MCP inspections.

Addedv1.16.0Oct 21, 2026

TDQS

A4.8/5.0

Behavior5/5

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

With no annotations, the description carries the full burden and does so: it declares the tool is never destructive, that restore first snapshots current state so it can be undone, and that versions are auto-created every 10 minutes plus before an agent's first edit or a set_project rewrite. These are non-obvious side effects an agent could not infer elsewhere.

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

Conciseness4/5

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

Front-loaded with the resource and the safety claim, then structured as an action list with inline guidance. It is dense and long for one paragraph, but nearly every clause carries actionable information; a bulleted layout would scan better.

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?

A 7-parameter, 6-action mutation tool with no annotations and no output schema — the description covers action semantics, side effects, defaults, consumers of version ids (fablecut_projects), and the human-visible consequence of restore. Nothing essential is missing for correct invocation.

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, but the description adds real meaning beyond it: which parameters belong to which action (save/diff/restore/update signatures), that project defaults to the open one, and that version accepts a number. The 'to' semantics for diff are useful too. It stops short of covering edge cases like 'final' uniqueness enforcement, which the schema mentions.

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 opening clause names the resource precisely (a project's version history, saved copies) and the description then enumerates all six actions with their payloads (list/save/diff/restore/update/delete). An agent can distinguish this from siblings like fablecut_projects or fablecut_set_project without opening a schema.

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?

Explicit triggers are given per action: save 'before big or risky edits, and when the user is happy with a cut', restore 'only when they asked', diff to see what changed. It also states the default (list) and warns that restoring changes what the user sees, which functions as a when-not rule.

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