---
title: "Plan a new trailer, free"
method: POST
path: "/conversations/{conversationId}/trailer-plan"
tags: ["trailer"]
---

# Plan a new trailer, free

`POST /conversations/{conversationId}/trailer-plan`

## Request

- Base URL: `https://docs.sleeperhit.studio/api/v1`
- URL: `https://docs.sleeperhit.studio/api/v1/conversations/{conversationId}/trailer-plan`
- Auth: HTTP bearer

Starts planning from this conversation's screenplay and scope. Stops at a draft: no render or credit reservation. A bound source keeps its thread, and the new cut gets a fresh subject conversation. notes is explicit new-cut direction only. An in-flight plan returns planning false/alreadyRunning true and creates no thread. Poll storyJobId; approve_trailer_plan separately quotes rendering.

## Headers

- `Idempotency-Key` string, required

## Request body

- object
  - `notes` string
  - `targetSeconds` integer
  - `aspectRatio` '9:16' | '16:9' | '1:1'
  - `shotDensity` 'held' | 'standard' | 'dense'
  - `title` string

## Response `200`

Planning started with its new conversation and storyJobId, or alreadyRunning with the active job id.

- object
  - `planning` boolean, required
  - `alreadyRunning` boolean, required
  - `sourceConversationId` string, nullable, required
  - `status` string, required
  - `storyJobId` string
  - `runningStoryJobId` string
  - `conversation` object, nullable, required
    - `id` string
    - `slug` string
  - `nextStep` 'approve_trailer_plan'

## Other responses

- `400`: Request payload failed validation. The error message names the offending field.
- `401`: Missing, malformed, revoked, or expired API key.
- `403`: API key is valid but lacks the scope, is blocked by IP allowlist, or the account is disabled.
- `404`: The named project or source does not exist or is owned by another account.
- `429`: Rate limit for this API key + IP + route family was exceeded.
- `500`: The API failed unexpectedly. Safe to retry with the same Idempotency-Key.

---

[API](https://skmtc.dev/sleeperhit/apis/sleeper-hit-studio-story-api.md) · [All operations](https://skmtc.dev/sleeperhit/apis/sleeper-hit-studio-story-api/llms.txt) · [OpenAPI document](https://skmtc.dev/sleeperhit/apis/sleeper-hit-studio-story-api/revisions/86e084144cef?raw)