---
title: "Post Reply"
method: POST
path: "/writeup/comments/{thread_id}/replies"
tags: ["runtime_mutations", "writeup", "writeup"]
---

# Post Reply

`POST /writeup/comments/{thread_id}/replies`

## Path parameters

- `thread_id` string, uuid, required

## Query parameters

- `path` string, required

## Request body

- ReplyRequest
  - `id` string, uuid, required
  - `body` string, required
  - `mentions` CommentMention[]
    - `kind` 'agent' | 'user', required
    - `id` string, required
    - `name` string, required

## Response `200`

Successful Response

- unknown

## Other responses

- `422` — Validation Error

## Changes

- **2026-09-22** `397ad3a1d858` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/quadrillion/apis/quadrillion-cloud-api/changes/writeup/comments/:thread_id/replies/post.md)

---

[API](https://skmtc.dev/quadrillion/apis/quadrillion-cloud-api.md) · [All operations](https://skmtc.dev/quadrillion/apis/quadrillion-cloud-api/llms.txt) · [OpenAPI document](https://skmtc.dev/quadrillion/apis/quadrillion-cloud-api/revisions/d61e2ec5a271?raw)