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DestructiveIdempotent

Manage the cold open segment before a film's first frame: read current settings, set footage, duration, fades, and gain, or reset it entirely. Use plan to validate changes without writing.

Instructions

Read or change the cold open this project plays before its first frame.

tail's mirror at the other end of the film — the same read/partial- update/reset/plan shape — but its asset rule runs the other way: asset must be a registered clip_id, never card:name. A cold open is real footage with real dialogue by definition; tail forbids that because verify would gain a permanent disagreement it can never resolve, and a head is taught to account for its own words instead (verify's head_words_trimmed) rather than being restricted to silence. Call it with no arguments to read what is in force.

Setting asset or seconds for the first time needs both together; either alone after that updates just that field, tail's partial-update shape. src_start defaults to 0.0 on a first set. fade_in/fade_out default to 0.0 and — unlike tail's fade — are drawn from day one, the whole reason this feature exists (a hard butt-join between room tone and digital silence is exactly the seam a missing fade produces). gain_db defaults to 0.0, a flat non-fading level shift distinct from the fades.

Needs an existing picture cue lane covering the whole film, tail's own requirement — add cues first (cue_add) if the project does not have one. reset drops the head entirely. plan resolves and validates without writing.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
pathNoThe 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.
planNoResolve the whole call and report what it would do, writing nothing. Prefer it over doing the thing and undoing it.
assetNoThe footage the cold open plays, as a registered clip id — never `card:name`. A cold open is real footage with real dialogue by definition, and `verify` accounts for its words rather than forbidding them.
resetNoDrop the cold open entirely.
fade_inNoSeconds of fade at the head. Unlike `tail`'s fade this is drawn, and it is the whole reason the feature exists — a hard butt-join between room tone and digital silence is exactly the seam a missing fade produces.
gain_dbNoA flat level shift for the cold open, in dB, distinct from the fades. 0.0 is unity.
secondsNoHow long the cold open runs. Setting `asset` or `seconds` for the first time needs both together; either alone afterwards updates just that field.
fade_outNoSeconds of fade where the cold open hands over to the film.
src_startNoWhere inside that asset the cold open reads from, in source seconds. 0.0 on a first set.

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault

No arguments

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed33 schema fields changedv0.25.0
    • removedInput schema / properties / asset / anyOf
      Removed value: -[
      -  {
      -    "type": "string"
      -  },
      -  {
      -    "type": "null"
      -  }
      -]
    • addedInput schema / properties / asset / description
      Added value: +"The footage the cold open plays, as a registered clip id — never `card:name`. A cold open is real footage with real dialogue by definition, and `verify` accounts for its words rather than forbidding them."
    • removedInput schema / properties / asset / title
      Removed value: -"Asset"
    • addedInput schema / properties / asset / type
      Added value: +[
      +  "string",
      +  "null"
      +]
    • removedInput schema / properties / fade_in / anyOf
      Removed value: -[
      -  {
      -    "type": "number"
      -  },
      -  {
      -    "type": "null"
      -  }
      -]
    • addedInput schema / properties / fade_in / description
      Added value: +"Seconds of fade at the head. Unlike `tail`'s fade this is drawn, and it is the whole reason the feature exists — a hard butt-join between room tone and digital silence is exactly the seam a missing fade produces."
    • removedInput schema / properties / fade_in / title
      Removed value: -"Fade In"
    • addedInput schema / properties / fade_in / type
      Added value: +[
      +  "number",
      +  "null"
      +]
    • removedInput schema / properties / fade_out / anyOf
      Removed value: -[
      -  {
      -    "type": "number"
      -  },
      -  {
      -    "type": "null"
      -  }
      -]
    • addedInput schema / properties / fade_out / description
      Added value: +"Seconds of fade where the cold open hands over to the film."
    • removedInput schema / properties / fade_out / title
      Removed value: -"Fade Out"
    • addedInput schema / properties / fade_out / type
      Added value: +[
      +  "number",
      +  "null"
      +]
    • removedInput schema / properties / gain_db / anyOf
      Removed value: -[
      -  {
      -    "type": "number"
      -  },
      -  {
      -    "type": "null"
      -  }
      -]
    • addedInput schema / properties / gain_db / description
      Added value: +"A flat level shift for the cold open, in dB, distinct from the fades. 0.0 is unity."
    • removedInput schema / properties / gain_db / title
      Removed value: -"Gain Db"
    • addedInput schema / properties / gain_db / type
      Added value: +[
      +  "number",
      +  "null"
      +]
    • 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 cold open entirely."
    • removedInput schema / properties / reset / title
      Removed value: -"Reset"
    • removedInput schema / properties / seconds / anyOf
      Removed value: -[
      -  {
      -    "type": "number"
      -  },
      -  {
      -    "type": "null"
      -  }
      -]
    • addedInput schema / properties / seconds / description
      Added value: +"How long the cold open runs. Setting `asset` or `seconds` for the first time needs both together; either alone afterwards updates just that field."
    • removedInput schema / properties / seconds / title
      Removed value: -"Seconds"
    • addedInput schema / properties / seconds / type
      Added value: +[
      +  "number",
      +  "null"
      +]
    • removedInput schema / properties / src_start / anyOf
      Removed value: -[
      -  {
      -    "type": "number"
      -  },
      -  {
      -    "type": "null"
      -  }
      -]
    • addedInput schema / properties / src_start / description
      Added value: +"Where inside that asset the cold open reads from, in source seconds. 0.0 on a first set."
    • removedInput schema / properties / src_start / title
      Removed value: -"Src Start"
    • addedInput schema / properties / src_start / type
      Added value: +[
      +  "number",
      +  "null"
      +]
    • removedInput schema / title
      Removed value: -"headArguments"
  2. First observedv0.24.0

TDQS

A4.8/5.0
Behavior5/5

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

Although annotations already mark the tool as destructive and idempotent, the description goes far beyond them: it explains partial-update semantics, `reset` dropping the head entirely, `plan` resolving without writing, the cue-lane prerequisite, and the reason fades are drawn from day one. This is rich behavioral context beyond the structured fields.

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?

The description is longer than average but each paragraph covers a distinct operational rule: reading, partial updates, defaults, prerequisites, reset, and plan. It is front-loaded with the core purpose; the additional rationale is dense but mostly 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?

Given the tool's complexity, the rich parameter schema, and annotations, the description covers all necessary invocation modes, preconditions, defaults, and sibling-tool relationships. The output schema exists, so the lack of return-value detail is not a gap. Nothing essential for calling 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, and the schema itself already documents each parameter. The description adds real value by explaining interdependencies — `asset` and `seconds` must be set together on first set — and by clarifying defaults like `src_start` at 0.0 and the distinction between `gain_db` and the fades.

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 and resource: "Read or change the cold open this project plays before its first frame." It clearly distinguishes the tool from `tail` by calling it that tool's mirror at the other end of the film, so an agent can tell them apart immediately.

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 invocation guidance: call with no arguments to read, set asset and seconds together on first set, update individually afterward, use `plan` to validate without writing, and `cue_add` first if no picture cue lane exists. It also names `tail` and `verify` as related tools, making the when-to-use boundary clear.

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