Inbox

Reply publicly

Answers the comment or mention on the platform, as the account it was addressed to, and marks it replied.

POST/v1/inbox/{id}/reply

TL;DR

Question	Answer
What does it do?	Reply publicly.
What does it need?	An API key or an OAuth access token.
What does it take?	A JSON body with the fields below, and `id` in the path.
What does it return?	Status 200 with a body of type `InboxItem`.
In the SDK?	`flung.inbox.reply()`
As an MCP tool?	`reply_to_inbox_item`
What can go wrong?	`401` Missing, unknown, revoked or expired API key; `404` No such item in this workspace; `422` The request failed validation; `429` Too many requests for this credential; wait for `retry-after` seconds. Every failure has the same error shape.

Example

1curl -X POST 'https://api.flung.dev/v1/inbox/ibx_aaaaaaaaaaaaaaaaaaaaaaaa/reply' \2  --header "Authorization: Bearer $FLUNG_API_KEY" \3  --header 'Content-Type: application/json' \4  --header "Idempotency-Key: $(uuidgen)" \5  --data '{6  "text": "string"7}'

1import { Flung } from '@flung.dev/sdk'2
3const flung = new Flung({ apiKey: process.env.FLUNG_API_KEY! })4const result = await flung.inbox.reply({5  id: 'ibx_aaaaaaaaaaaaaaaaaaaaaaaa',6  text: 'string',7})

1const response = await fetch('https://api.flung.dev/v1/inbox/ibx_aaaaaaaaaaaaaaaaaaaaaaaa/reply', {2  method: 'POST',3  headers: {4    'Authorization': `Bearer ${process.env.FLUNG_API_KEY}`,5    'Content-Type': 'application/json',6    'Idempotency-Key': crypto.randomUUID(),7  },8  body: JSON.stringify({9    text: 'string',10  }),11})12if (!response.ok) throw new Error((await response.json()).error.message)13const result = await response.json()

A successful answer looks like this:

1{2  "id": "ibx_aaaaaaaaaaaaaaaaaaaaaaaa",3  "accountId": "string",4  "platform": "x",5  "kind": "comment",6  "status": "unread",7  "text": "string",8  "author": {9    "id": "string",10    "name": "string",11    "handle": "string"12  },13  "url": "string",14  "platformItemId": "string",15  "platformPostId": "string",16  "targetId": "string",17  "createdAt": "2026-11-01T09:00:00.000Z",18  "repliedAt": "2026-11-01T09:00:00.000Z"19}

Path parameters

Field	Type	Required	Description
`id`	`string`	yes

Request body

The body has the type an object, with the fields below.

Field	Type	Required	Description
`text`	`string`	yes	at least 1 character; at most 10000 characters.

Responses

Status	Meaning	Body
200	The item, replied.	`InboxItem`
401	Missing, unknown, revoked or expired API key.	`Error`
404	No such item in this workspace.	`Error`
422	The request failed validation.	`Error`
429	Too many requests for this credential; wait for `retry-after` seconds.	`Error`

Response body

A 200 answer has the type InboxItem.

Field	Type	Required	Description
`id`	`string`	yes
`accountId`	`string`	yes
`platform`	`Platform`	yes
`kind`	`"comment" \| "mention"`	yes	`comment`: a reply to one of the account's posts. `mention`: the account named elsewhere.
`status`	`"unread" \| "read" \| "replied" \| "archived"`	yes
`text`	`string`	yes
`author`	`object`	yes
`author.id`	`string`	yes
`author.name`	`string \| null`	yes
`author.handle`	`string \| null`	yes
`url`	`string \| null`	yes
`platformItemId`	`string`	yes
`platformPostId`	`string \| null`	yes	The platform post it answers.
`targetId`	`string \| null`	yes	The Flung post target it answers, when that post went out through Flung.
`createdAt`	`string`	yes
`repliedAt`	`string \| null`	yes

Doc	Why
API reference	Every endpoint
Schemas	Every request and response type
Errors	Every error code and what to do about it
`reply_to_inbox_item`	The same operation as an MCP tool