Kernel Extensions API
Create, list, retrieve, and delete browser extensions.
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OpenAPI Specification
openapi: 3.2.0
info:
description: Developer tools and cloud infrastructure for AI agents to use web browsers
title: Kernel Extensions API
version: 0.1.0
servers:
- description: API Server
url: https://api.onkernel.com
security:
- bearerAuth: []
tags:
- description: Create, list, retrieve, and delete browser extensions.
name: Extensions
paths:
/extensions:
get:
description: List extensions in the resolved project.
operationId: getExtensions
parameters:
- description: Limit the number of extensions to return.
in: query
name: limit
required: false
schema:
default: 20
maximum: 100
minimum: 1
type: integer
- description: Offset the number of extensions to return.
in: query
name: offset
required: false
schema:
default: 0
minimum: 0
type: integer
- description: Case-insensitive substring match against extension name. IDs match by exact value.
in: query
name: query
required: false
schema:
type: string
- description: Exact-match filter on extension name using the database collation. In production, matching is case- and accent-insensitive. During the default-project migration, unscoped requests prefer a concrete default-project extension over a legacy unscoped extension with the same name.
in: query
name: name
required: false
schema:
type: string
responses:
'200':
content:
application/json:
schema:
items:
$ref: '#/components/schemas/Extension'
type: array
description: List of extensions
headers:
X-Has-More:
description: Whether there are more extensions to fetch.
schema:
default: false
type: boolean
X-Limit:
description: Limit the number of extensions to return.
schema:
default: 20
maximum: 100
minimum: 1
type: integer
X-Next-Offset:
description: The offset where the next page starts. 0 when there are no more results.
schema:
nullable: true
type: integer
X-Offset:
description: The offset of extensions to return.
schema:
default: 0
minimum: 0
type: integer
'401':
$ref: '#/components/responses/Unauthorized'
'500':
$ref: '#/components/responses/InternalError'
security:
- bearerAuth: []
summary: List browser extensions
tags:
- Extensions
post:
description: Upload a zip file containing an unpacked browser extension. Optionally provide a unique name for later reference.
operationId: postExtensions
requestBody:
content:
multipart/form-data:
schema:
properties:
file:
description: ZIP file containing the browser extension.
example: '@path/to/extension.zip'
format: binary
type: string
name:
description: Optional unique name within the project to reference this extension.
pattern: ^[A-Za-z0-9._-]{1,255}$
type: string
required:
- file
type: object
required: true
responses:
'201':
content:
application/json:
schema:
$ref: '#/components/schemas/Extension'
description: Extension uploaded successfully
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
'403':
$ref: '#/components/responses/Forbidden'
'409':
$ref: '#/components/responses/Conflict'
'500':
$ref: '#/components/responses/InternalError'
security:
- bearerAuth: []
summary: Upload a browser extension
tags:
- Extensions
/extensions/from_chrome_store:
get:
description: Returns a ZIP archive containing the unpacked extension fetched from the Chrome Web Store.
operationId: getExtensionsFromChromeStore
parameters:
- description: Chrome Web Store URL for the extension.
in: query
name: url
required: true
schema:
type: string
- description: Target operating system for the extension package. Defaults to linux.
in: query
name: os
required: false
schema:
default: linux
enum:
- win
- mac
- linux
type: string
responses:
'200':
content:
application/octet-stream:
schema:
format: binary
type: string
description: Extension ZIP archive
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
'403':
$ref: '#/components/responses/Forbidden'
'500':
$ref: '#/components/responses/InternalError'
security:
- bearerAuth: []
summary: Download unpacked extension from Chrome Web Store
tags:
- Extensions
/extensions/{id_or_name}:
delete:
description: Delete an extension by its ID or by its name.
operationId: deleteExtensionByIdOrName
parameters:
- description: Extension ID or extension name
in: path
name: id_or_name
required: true
schema:
type: string
responses:
'204':
description: Extension deleted successfully
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
'500':
$ref: '#/components/responses/InternalError'
security:
- bearerAuth: []
summary: Delete extension by ID or name
tags:
- Extensions
get:
description: Download the extension as a ZIP archive by ID or name.
operationId: getExtensionByIdOrName
parameters:
- description: Extension ID or name
in: path
name: id_or_name
required: true
schema:
type: string
responses:
'200':
content:
application/octet-stream:
schema:
format: binary
type: string
description: Extension ZIP archive
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
'500':
$ref: '#/components/responses/InternalError'
security:
- bearerAuth: []
summary: Download extension archive
tags:
- Extensions
/extensions/{id_or_name}/metadata:
get:
description: Get an extension's metadata (name, size, timestamps) by ID or name, without downloading the archive.
operationId: getExtensionByIdOrNameMetadata
parameters:
- description: Extension ID or name
in: path
name: id_or_name
required: true
schema:
type: string
responses:
'200':
content:
application/json:
schema:
$ref: '#/components/schemas/Extension'
description: Extension metadata
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
'500':
$ref: '#/components/responses/InternalError'
security:
- bearerAuth: []
summary: Get extension metadata
tags:
- Extensions
components:
responses:
NotFound:
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
description: Resource not found
BadRequest:
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
description: Bad Request – invalid input
Conflict:
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
description: Conflict – resource already exists
InternalError:
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
description: Internal Server Error
Forbidden:
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
description: Forbidden – insufficient permissions or plan
Unauthorized:
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
description: Unauthorized – missing or invalid authorization token
schemas:
Extension:
description: A browser extension uploaded to Kernel.
properties:
checksum:
description: SHA-256 checksum, encoded as lowercase hexadecimal, of the exact uploaded extension archive bytes. This is not a normalized checksum of the extension contents; archive metadata, file ordering, and compression can change the checksum for otherwise identical contents. Omitted for legacy rows and server-repackaged Chrome Web Store extensions.
maxLength: 64
minLength: 64
nullable: true
type: string
created_at:
description: Timestamp when the extension was created
format: date-time
type: string
id:
description: Unique identifier for the extension
type: string
last_used_at:
description: Timestamp when the extension was last used
format: date-time
nullable: true
type: string
name:
description: Optional, easier-to-reference name for the extension. Must be unique within the project.
nullable: true
type: string
size_bytes:
description: Size of the extension archive in bytes
type: integer
required:
- id
- created_at
- size_bytes
type: object
ErrorDetail:
properties:
code:
description: Lower-level error code providing more specific detail
example: invalid_input
type: string
message:
description: Further detail about the error
example: Provided version string is not semver compliant
type: string
type: object
Error:
properties:
code:
description: Application-specific error code (machine-readable)
example: bad_request
type: string
details:
description: Additional error details (for multiple errors)
items:
$ref: '#/components/schemas/ErrorDetail'
type: array
inner_error:
$ref: '#/components/schemas/ErrorDetail'
message:
description: Human-readable error description for debugging
example: 'Missing required field: app_name'
type: string
required:
- code
- message
type: object
securitySchemes:
bearerAuth:
scheme: bearer
type: http
x-service-info:
categories:
- browsers
docs:
apiReference: https://www.kernel.sh/docs
homepage: https://www.kernel.sh
llms: https://api.onkernel.com/llms.txt
x-provenance:
method: harvested
publisher: Kernel
source: https://api.onkernel.com/openapi.json
note: split by refine-openapis from the provider's own published document, verified by fetch (openapi/_original/*.fetch.json);
stamped by stamp-openapi-provenance.py (roadmap#793)