---
title: "Preview Auto Router Classifier Prompt"
method: POST
path: "/auto_router/classifier/default_prompt"
tags: ["model management"]
---

# Preview Auto Router Classifier Prompt

`POST /auto_router/classifier/default_prompt`

Get the system prompt an auto-router's LLM classifier sends for an edited tier set

## Request body

- AutoRouterClassifierPromptPreviewRequest — A POST rather than query params: the classification sections are the operator's own text, which must not reach access logs through a URL.
  - `tier_definitions` TierDefinition[], nullable
    - `name` string, required — Tier name; becomes a value the LLM classifier can return and a key of `tiers`
    - `description` string, nullable — What belongs in this tier; rendered as this tier's bullet in the classifier rubric. Required unless the name is a built-in tier (SIMPLE/MEDIUM/COMPLEX/REASONING), which inherits the built-in criteria when omitted
  - `tier_labels` object, nullable
  - `classification_rubric` 'legacy' | 'agentic' | 'chat' | 'business' — Which calibration examples, and for BUSINESS which tier criteria, the built-in classifier rubric carries.
  - `context_window_size` integer
  - `classification_prompt` string, nullable
  - `classification_examples` string, nullable

## Response `200`

Successful Response

- AutoRouterClassifierDefaultPromptResponse — The built-in system prompt an auto-router's LLM classifier uses when none is configured. Served so the dashboard's prompt editor prefills the rubric the proxy actually sends, rather than a copy in the frontend that drifts the moment the rubric is edited.
  - `system_prompt` string, required

## Other responses

- `422` — Validation Error

## Changes

- **2026-09-18** `082b5fabd909` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/flock/apis/litellm-api/changes/auto_router/classifier/default_prompt/post.md)

---

[API](https://skmtc.dev/flock/apis/litellm-api.md) · [All operations](https://skmtc.dev/flock/apis/litellm-api/llms.txt) · [OpenAPI document](https://skmtc.dev/flock/apis/litellm-api/revisions/3b2b241e4b0b?raw)