---
title: "Get Attachment Thumbnail"
method: GET
path: "/chat/messages/{message_id}/attachment/thumbnail"
tags: ["chat"]
---

# Get Attachment Thumbnail

`GET /chat/messages/{message_id}/attachment/thumbnail`

## Request

- Base URL: `https://api.projectindi.com` (the document declares no server; this is the origin it was published from)
- URL: `https://api.projectindi.com/chat/messages/{message_id}/attachment/thumbnail`
- Auth: none declared

Get a sized thumbnail URL for a chat message attachment.

Lazy uploads base64 attachment to storage on first request, then mints a
sized image URL (assets Worker on R2, else imgproxy) for efficient mobile
display. Falls back to a raw signed URL if minting fails.

Authentication: JWT required
RLS: User must have access to the message

## Path parameters

- `message_id` string, required

## Query parameters

- `index` integer: Attachment index (default: first)
- `width` integer: Thumbnail width
- `height` integer, nullable: Thumbnail height (omit for a square: height = width)

## Response `200`

Successful Response

- unknown

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/projectindi/apis/indi-agent-api-first-principles.md) - [All operations](https://skmtc.dev/projectindi/apis/indi-agent-api-first-principles/llms.txt) - [OpenAPI document](https://skmtc.dev/projectindi/apis/indi-agent-api-first-principles/revisions/25a7813e21fd?raw)