Enterprise Files

Upload and manage files within a workspace — reference documents, spreadsheets, images, and PDFs that your AI agents can read, reason over, and cite.

Files are stored in private Cloudflare R2 object storage. The API server never receives file bytes — instead, the server validates your metadata and issues a presigned PUT URL, and your client uploads directly to R2. This keeps the API lean, eliminates file size constraints from the HTTP gateway, and scales to concurrent uploads without bottlenecks.

How It Works

1. POST /files/presign       → server validates metadata, returns { fileId, uploadUrl, expiresAt }
2. PUT  <uploadUrl>          → client uploads file bytes directly to R2 (no Authorization header)
3. POST /files/:id/confirm   → server verifies the upload succeeded, marks file ready

The presigned uploadUrl has a 1-hour TTL by default. The Content-Type and Content-Length are cryptographically locked into the URL — R2 will reject uploads with mismatched MIME type or byte count.

Once confirmed, you can attach files to AI sessions and messages using their fileId.

Workspace Context Required

All file operations require a workspace context. Pass the x-workspace-id header. Files belong to a workspace and are visible to all workspace members.

Role Requirements

Operation	Required Role
Upload (presign + confirm)	`member`, `admin`, or `owner`
List, get, download	Any authenticated member
Update metadata	`member`, `admin`, or `owner`
Delete own file	`member`, `admin`, or `owner`
Delete another member's file	`admin` or `owner` only

Endpoints

Method	Path	Description	Auth	Rate Limit
POST	`/files/presign`	Initiate upload — get presigned PUT URL	JWT	10/min
POST	`/files/:id/confirm`	Confirm upload completed	JWT	10/min
GET	`/files`	List ready files	JWT	60/min
GET	`/files/:id`	Get file metadata	JWT	60/min
GET	`/files/:id/download`	Get presigned download URL	JWT	60/min
PATCH	`/files/:id`	Update purpose / metadata	JWT	30/min
DELETE	`/files/:id`	Delete file from storage and records	JWT	30/min

Complete Upload Walkthrough

Here is the full three-step upload flow in one code block — the most common pattern you will use.

JavaScriptPython

javascript

// Step 1 — Request a presigned URL
const presignRes = await fetch(`${BASE_URL}/files/presign`, {
  method: "POST",
  headers: {
    Authorization: `Bearer ${TOKEN}`,
    "Content-Type": "application/json",
    "x-workspace-id": WORKSPACE_ID,
  },
  body: JSON.stringify({
    originalName: file.name,          // "vocabulary-list.csv"
    mimeType: file.type,              // "text/csv"
    sizeBytes: file.size,             // exact byte count
    purpose: "session-attachment",    // optional label
  }),
});
const { data } = await presignRes.json();
// data.fileId   — store this, you'll need it
// data.uploadUrl — presigned R2 URL
// data.expiresAt — ISO 8601, URL expires at this time

// Step 2 — Upload directly to R2 (no Authorization header)
await fetch(data.uploadUrl, {
  method: "PUT",
  headers: {
    "Content-Type": file.type,        // must match what you sent to /presign
    "Content-Length": String(file.size), // must match what you sent to /presign
  },
  body: file, // File or Blob
});

// Step 3 — Confirm the upload
const confirmRes = await fetch(`${BASE_URL}/files/${data.fileId}/confirm`, {
  method: "POST",
  headers: {
    Authorization: `Bearer ${TOKEN}`,
    "Content-Type": "application/json",
    "x-workspace-id": WORKSPACE_ID,
  },
  body: JSON.stringify({}),
});
const { data: fileRecord } = await confirmRes.json();
console.log(fileRecord.status); // "ready"

python

import requests

# Step 1 — Request a presigned URL
file_path = "vocabulary-list.csv"
with open(file_path, "rb") as f:
    file_bytes = f.read()

presign = requests.post(
    f"{BASE_URL}/files/presign",
    headers={
        "Authorization": f"Bearer {TOKEN}",
        "x-workspace-id": WORKSPACE_ID,
    },
    json={
        "originalName": "vocabulary-list.csv",
        "mimeType": "text/csv",
        "sizeBytes": len(file_bytes),
        "purpose": "session-attachment",
    },
)
data = presign.json()["data"]

# Step 2 — Upload directly to R2
requests.put(
    data["uploadUrl"],
    data=file_bytes,
    headers={
        "Content-Type": "text/csv",
        "Content-Length": str(len(file_bytes)),
    },
)

# Step 3 — Confirm the upload
confirm = requests.post(
    f"{BASE_URL}/files/{data['fileId']}/confirm",
    headers={
        "Authorization": f"Bearer {TOKEN}",
        "x-workspace-id": WORKSPACE_ID,
    },
    json={},
)
file_record = confirm.json()["data"]
print(file_record["status"])  # "ready"

POST /files/presign

Validate file metadata and receive a presigned PUT URL for direct upload to R2.

Authentication: JWT Bearer token
Rate limit: 10/min

Request

Request Body

Field	Type	Required	Constraints	Description
`originalName`	string	Yes	Max 255 characters	Filename as shown to the user
`mimeType`	string	Yes	`text/csv`, `text/plain`, `application/pdf`, `image/png`, `image/jpeg`	MIME type of the file
`sizeBytes`	number	Yes	1 – 10,485,760 (10 MB)	Exact byte count of the file
`purpose`	string	No	Max 100 characters, default: `general`	Intended use (e.g. `session-attachment`)

Response

Response Example

json

{
  "data": {
    "fileId": "018e1234-5678-7abc-9def-012345678901",
    "uploadUrl": "https://chainabit-prod-files.account-id.r2.cloudflarestorage.com/...",
    "expiresAt": "2026-03-17T11:00:00.000Z"
  }
}

Response Fields

Field	Type	Description
`fileId`	string	File record ID — use in subsequent requests
`uploadUrl`	string	Presigned R2 PUT URL — upload bytes directly
`expiresAt`	string	ISO 8601 — URL expires at this time

Upload to R2

After receiving the presigned URL, PUT the file bytes directly:

bash

curl -X PUT "$UPLOAD_URL" \
  -H "Content-Type: text/csv" \
  -H "Content-Length: 15420" \
  --data-binary @vocabulary-list.csv

Important: No Authorization header is sent to R2 — the presigned URL carries all credentials. The Content-Type and Content-Length headers must exactly match what was specified in /presign, or R2 will reject the upload with 403 Forbidden.

Code Examples

cURLJavaScriptPython

bash

curl -X POST https://api.chainabit.com/api/v1/files/presign \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID" \
  -H "Content-Type: application/json" \
  -d '{
    "originalName": "vocabulary-list.csv",
    "mimeType": "text/csv",
    "sizeBytes": 15420,
    "purpose": "session-attachment"
  }'

javascript

const res = await fetch(`${BASE_URL}/files/presign`, {
  method: "POST",
  headers: {
    Authorization: `Bearer ${TOKEN}`,
    "x-workspace-id": WORKSPACE_ID,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    originalName: "vocabulary-list.csv",
    mimeType: "text/csv",
    sizeBytes: 15420,
    purpose: "session-attachment",
  }),
});
const { data } = await res.json();
// data.fileId, data.uploadUrl, data.expiresAt

python

import requests

res = requests.post(
    f"{BASE_URL}/files/presign",
    headers={
        "Authorization": f"Bearer {TOKEN}",
        "x-workspace-id": WORKSPACE_ID,
    },
    json={
        "originalName": "vocabulary-list.csv",
        "mimeType": "text/csv",
        "sizeBytes": 15420,
        "purpose": "session-attachment",
    },
)
data = res.json()["data"]

POST /files/:id/confirm

Confirm that the upload to R2 is complete. The server issues a HEAD request to R2 to verify the object exists before marking the file as ready. A file will only appear in listings after confirmation.

Authentication: JWT Bearer token
Rate limit: 10/min

Request

Request Body

Field	Type	Required	Description
`etag`	string	No	ETag returned by R2 after upload

Use the fileId from POST /files/presign's response (data.fileId) as $FILE_ID below.

Response

Response Example

json

{
  "data": {
    "id": "018e1234-5678-7abc-9def-012345678901",
    "originalName": "vocabulary-list.csv",
    "mimeType": "text/csv",
    "sizeBytes": "15420",
    "purpose": "session-attachment",
    "status": "ready",
    "workspaceId": "wsp_abc123",
    "createdAt": "2026-03-17T10:00:00.000Z",
    "confirmedAt": "2026-03-17T10:01:30.000Z"
  }
}

Error: Upload Not Found

If you call /confirm before completing the PUT upload to R2, the server will return:

json

{
  "statusCode": 400,
  "message": "Upload not found in storage. Complete the presigned PUT upload before confirming."
}

Always complete the R2 PUT before calling /confirm.

Code Examples

cURLJavaScriptPython

bash

curl -X POST https://api.chainabit.com/api/v1/files/$FILE_ID/confirm \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID" \
  -H "Content-Type: application/json" \
  -d '{}'

javascript

const res = await fetch(`${BASE_URL}/files/${fileId}/confirm`, {
  method: "POST",
  headers: {
    Authorization: `Bearer ${TOKEN}`,
    "x-workspace-id": WORKSPACE_ID,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({}),
});
const { data } = await res.json();

python

import requests

res = requests.post(
    f"{BASE_URL}/files/{file_id}/confirm",
    headers={
        "Authorization": f"Bearer {TOKEN}",
        "x-workspace-id": WORKSPACE_ID,
    },
    json={},
)
data = res.json()["data"]

GET /files

List files in the current workspace. Only ready and non-deleted files are returned. Results are ordered by upload date — newest first.

Files with private access scope are only visible to the uploader and workspace admins/owners.

Authentication: JWT Bearer token
Rate limit: 60/min

Request

Query Parameters

Parameter	Type	Default	Description
`q`	string (≤200)	—	Case-insensitive partial match on filename
`cursor`	string	—	Opaque pagination cursor from a previous response
`limit`	integer (1–100)	25	Number of results per page
`mediaType`	string	—	`image`, `audio`, `video`, `document`, or `other`
`accessScope`	string	—	`private`, `workspace`, or `account`
`processingState`	string	—	`raw`, `processed`, or `derived`
`purpose`	string	—	Exact-match on purpose label
`tags`	string	—	Comma-separated tag list — returns files matching any tag
`chainyId`	UUID	—	Filter to files attached to a specific chainy
`chainId`	UUID	—	Filter to files attached to a specific chain
`bitId`	UUID	—	Filter to files attached to a specific bit
`createdFrom`	ISO 8601	—	Lower bound on `createdAt`
`createdTo`	ISO 8601	—	Upper bound on `createdAt`
`updatedFrom`	ISO 8601	—	Lower bound on `updatedAt`
`updatedTo`	ISO 8601	—	Upper bound on `updatedAt`

Response

Response Example

json

{
  "data": {
    "items": [
      {
        "id": "018e1234-5678-7abc-9def-012345678901",
        "originalName": "vocabulary-list.csv",
        "mimeType": "text/csv",
        "mediaType": "document",
        "fileSizeBytes": "15420",
        "purpose": "session-attachment",
        "accessScope": "workspace",
        "processingState": "raw",
        "tags": [],
        "status": "ready",
        "workspaceId": "wsp_abc123",
        "createdAt": "2026-03-17T10:00:00.000Z",
        "confirmedAt": "2026-03-17T10:01:30.000Z",
        "updatedAt": "2026-03-17T10:01:30.000Z"
      }
    ],
    "nextCursor": null
  }
}

Response Fields

Field	Type	Description
`items`	array	Page of file records
`nextCursor`	string\|null	Pass as `cursor` in the next request to get the next page; `null` means no more pages
`id`	string	File ID
`originalName`	string	Filename provided at upload time
`mimeType`	string	MIME type
`mediaType`	string	`image`, `audio`, `video`, `document`, or `other`
`fileSizeBytes`	string	File size in bytes
`purpose`	string	Intended use label
`accessScope`	string	`private`, `workspace`, or `account`
`processingState`	string	`raw`, `processed`, or `derived`
`tags`	string[]	Tags attached to this file
`status`	string	Always `ready` in catalog listings
`workspaceId`	string	Workspace this file belongs to
`createdAt`	string	ISO 8601 — upload initiated
`confirmedAt`	string\|null	ISO 8601 — upload confirmed
`updatedAt`	string	ISO 8601 — last metadata update

Note: fileSizeBytes is a string because the database stores it as a bigint. Cast with parseInt(fileSizeBytes, 10) when needed.

Pagination

The catalog uses cursor-based pagination. Each page returns a nextCursor token. Pass it as ?cursor=<token> to fetch the next page. When nextCursor is null, you have reached the last page. Do not parse or store cursor internals — they are opaque and may change.

Code Examples

cURLJavaScriptPython

bash

# Search by filename
curl "https://api.chainabit.com/api/v1/files?q=vocabulary&limit=10" \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID"

# Filter by type + date range
curl "https://api.chainabit.com/api/v1/files?mediaType=document&createdFrom=2026-01-01T00:00:00Z" \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID"

# Paginate with cursor
curl "https://api.chainabit.com/api/v1/files?limit=25&cursor=$NEXT_CURSOR" \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID"

javascript

// Search by filename
const params = new URLSearchParams({ q: "vocabulary", limit: "10" });
const res = await fetch(`${BASE_URL}/files?${params}`, {
  headers: {
    Authorization: `Bearer ${TOKEN}`,
    "x-workspace-id": WORKSPACE_ID,
  },
});
const { data } = await res.json();
const { items, nextCursor } = data;

// Fetch next page
if (nextCursor) {
  const nextParams = new URLSearchParams({ limit: "10", cursor: nextCursor });
  const nextRes = await fetch(`${BASE_URL}/files?${nextParams}`, {
    headers: { Authorization: `Bearer ${TOKEN}`, "x-workspace-id": WORKSPACE_ID },
  });
}

python

import requests

# Search by filename
res = requests.get(
    f"{BASE_URL}/files",
    headers={
        "Authorization": f"Bearer {TOKEN}",
        "x-workspace-id": WORKSPACE_ID,
    },
    params={"q": "vocabulary", "limit": 10},
)
body = res.json()
items = body["data"]["items"]
next_cursor = body["data"].get("nextCursor")

GET /files/:id

Get metadata for a single file.

Authentication: JWT Bearer token
Rate limit: 60/min

Request

Path params: id

Response

Returns 403 Forbidden if the file belongs to another account — never 404 — to prevent existence probing across tenants.

Code Example

bash

curl https://api.chainabit.com/api/v1/files/$FILE_ID \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID"

GET /files/:id/download

Get a presigned download URL. The URL points directly to R2 — no Authorization header is needed to download. Only files in ready status can be downloaded.

Authentication: JWT Bearer token
Rate limit: 60/min

Request

Path params: id

Response

Response Example

json

{
  "data": {
    "downloadUrl": "https://chainabit-prod-files.account-id.r2.cloudflarestorage.com/...",
    "expiresAt": "2026-03-17T11:00:00.000Z"
  }
}

Tip: Download URLs expire after 1 hour. Do not cache them. Request a fresh URL from this endpoint each time you need to download or display a file.

Code Example

bash

curl https://api.chainabit.com/api/v1/files/$FILE_ID/download \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID"

PATCH /files/:id

Update a file's display name, purpose, and/or metadata. Does not affect the stored object in R2.

Authentication: JWT Bearer token
Rate limit: 30/min

Request

Request Body

Field	Type	Required	Description
`originalName`	string	No	New display name for the file
`purpose`	string	No	New purpose label
`metadata`	object	No	Arbitrary key-value metadata

Tip — AI analysis quality: When a file is later attached to an AI session, the resolver reads originalName and purpose from the database and surfaces them to the model as low-priority context. The model still analyzes the file directly; the filename and purpose serve as optional hints about the user's intent. Setting a meaningful purpose (e.g. "critique typography and color contrast") often produces more relevant analysis. The hint never overrides the user's actual question.

Response

Returns the updated file record — same shape as POST /files/:id/confirm's response, with the updated originalName, purpose, and/or metadata.

Code Example

bash

curl -X PATCH https://api.chainabit.com/api/v1/files/$FILE_ID \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID" \
  -H "Content-Type: application/json" \
  -d '{ "purpose": "critique typography and color contrast" }'

DELETE /files/:id

Delete a file. The object is permanently removed from R2 storage and the record is marked deleted. This operation is idempotent — calling it on an already-deleted file returns 200.

Members can delete their own files. Admins and owners can delete any file in the workspace.

Authentication: JWT Bearer token
Rate limit: 30/min

Request

Path params: id

Response

json

{ "data": null }

Code Example

bash

curl -X DELETE https://api.chainabit.com/api/v1/files/$FILE_ID \
  -H "Authorization: Bearer $TOKEN" \
  -H "x-workspace-id: $WORKSPACE_ID"

File Lifecycle

presign → [pending] → PUT to R2 → confirm → [ready] → delete → [deleted]

Status	Description
`pending`	Record created, upload not yet confirmed. Not visible in `GET /files`.
`ready`	Upload confirmed and verified. Available for use in sessions and downloads.
`deleted`	Permanently removed from R2. Record is retained for audit purposes.

Error Reference

Status	Code	When it occurs
400	`BAD_REQUEST`	Invalid MIME type, file too large, wrong state for operation
401	`UNAUTHORIZED`	Missing or expired JWT token
403	`FORBIDDEN`	File belongs to another account, or insufficient role for the operation
404	`NOT_FOUND`	File ID does not exist
429	`TOO_MANY_REQUESTS`	Rate limit exceeded for the endpoint

Notes

No multipart/form-data — files are uploaded directly to R2 via a presigned PUT URL. The API server never buffers file bytes.
Content-Type enforcement — the MIME type and file size are cryptographically locked into the presigned URL. R2 rejects uploads with mismatched values with 403 Forbidden.
Pending files — files remain pending until /confirm succeeds. They are not returned by GET /files and cannot be downloaded.
Private access — no file is ever publicly accessible. Downloads require a fresh presigned URL from the API.
Tenant isolation — all files are scoped to the authenticated account. Requests for another account's files return 403, not 404.
sizeBytes is a string — the database stores file size as bigint; the API serializes it as a string to avoid JavaScript precision loss for very large values. Cast with parseInt when needed.
Allowed MIME types: text/csv, text/plain, application/pdf, image/png, image/jpeg
Maximum file size: 10 MB (10,485,760 bytes)
Presigned URL TTL: 1 hour

Enterprise Files ​

How It Works ​

Workspace Context Required ​

Role Requirements ​

Endpoints ​

Complete Upload Walkthrough ​

POST /files/presign ​

Request ​

Request Body ​

Response ​

Response Example ​

Response Fields ​

Upload to R2 ​

Code Examples ​

POST /files/:id/confirm ​

Request ​

Request Body ​

Response ​

Response Example ​

Error: Upload Not Found ​

Code Examples ​

GET /files ​

Request ​

Query Parameters ​

Response ​

Response Example ​

Response Fields ​

Pagination ​

Code Examples ​

GET /files/:id ​

Request ​

Response ​

Code Example ​

GET /files/:id/download ​

Request ​

Response ​

Response Example ​

Code Example ​

PATCH /files/:id ​

Request ​

Request Body ​

Response ​

Code Example ​

DELETE /files/:id ​

Request ​

Response ​

Code Example ​

File Lifecycle ​

Error Reference ​

Notes ​

Enterprise Files

How It Works

Workspace Context Required

Role Requirements

Endpoints

Complete Upload Walkthrough

POST /files/presign

Request

Request Body

Response

Response Example

Response Fields

Upload to R2

Code Examples

POST /files/:id/confirm

Request

Request Body

Response

Response Example

Error: Upload Not Found

Code Examples

GET /files

Request

Query Parameters

Response

Response Example

Response Fields

Pagination

Code Examples

GET /files/:id

Request

Response

Code Example

GET /files/:id/download

Request

Response

Response Example

Code Example

PATCH /files/:id

Request

Request Body

Response

Code Example

DELETE /files/:id

Request

Response

Code Example

File Lifecycle

Error Reference

Notes