WorkspaceFilesystem

Added in: @mastra/core@1.1.0

The WorkspaceFilesystem interface defines how workspaces interact with file storage.

Methods

readFile(path, options?)

Read file contents.

const content = await filesystem.readFile('/docs/guide.md')
const buffer = await filesystem.readFile('/image.png', { encoding: 'binary' })

Parameters:

path:

string

File path relative to basePath

options?:

Options

readFile options.

Options

encoding?:

'utf-8' | 'binary'

Text or binary encoding

Returns: Promise<string | Buffer>

writeFile(path, content, options?)

Write file contents.

await filesystem.writeFile('/docs/new.md', '# New Document')
await filesystem.writeFile('/nested/path/file.md', content, { recursive: true })

Parameters:

path:

string

File path relative to basePath

content:

string | Buffer

File content

options?:

Options

Configuration options.

Options

recursive?:

boolean

Create parent directories if they don't exist

overwrite?:

boolean

Overwrite existing file

expectedMtime?:

Date

If provided, the write fails with a StaleFileError when the file's current modification time doesn't match. Use this for optimistic concurrency control to detect external modifications between read and write.

deleteFile(path, options?)

Delete a file.

await filesystem.deleteFile('/docs/old.md')
await filesystem.deleteFile('/docs/maybe.md', { force: true }) // Don't throw if missing

Parameters:

path:

string

File path

options?:

Options

Configuration options.

Options

force?:

boolean

Don't throw error if file doesn't exist

appendFile(path, content)

Append content to a file, creating it if it doesn't already exist. Parent directories are created automatically.

await filesystem.appendFile('/logs/app.log', 'New log entry\n')

Parameters:

path:

string

File path

content:

string | Buffer

Content to append

copyFile(src, dest, options?)

Copy a file to a new location.

await filesystem.copyFile('/docs/template.md', '/docs/new-doc.md')

Parameters:

src:

string

Source file path

dest:

string

Destination file path

options?:

Options

Configuration options.

Options

overwrite?:

boolean

Overwrite destination if it exists

moveFile(src, dest, options?)

Move or rename a file.

await filesystem.moveFile('/docs/draft.md', '/docs/final.md')

Parameters:

src:

string

Source file path

dest:

string

Destination file path

options?:

Options

Configuration options.

Options

overwrite?:

boolean

Overwrite destination if it exists

readdir(path, options?)

List directory contents.

const entries = await filesystem.readdir('/docs')
// [{ name: 'guide.md', type: 'file' }, { name: 'api', type: 'directory' }]

Returns: Promise<FileEntry[]>

interface FileEntry {
  name: string
  type: 'file' | 'directory'
  size?: number
  isSymlink?: boolean
  symlinkTarget?: string
}

mkdir(path, options?)

Create a directory.

await filesystem.mkdir('/docs/api')
await filesystem.mkdir('/deeply/nested/path', { recursive: true })

Parameters:

path:

string

Directory path

options?:

Options

Configuration options.

Options

recursive?:

boolean

Create parent directories

rmdir(path, options?)

Remove a directory.

await filesystem.rmdir('/docs/old')
await filesystem.rmdir('/docs/nested', { recursive: true })

Parameters:

path:

string

Directory path

options?:

Options

Configuration options.

Options

recursive?:

boolean

Remove contents recursively

force?:

boolean

Don't throw if directory doesn't exist

exists(path)

Check if a path exists.

const exists = await filesystem.exists('/docs/guide.md')

Returns: Promise<boolean>

stat(path)

Get file or directory metadata.

const stat = await filesystem.stat('/docs/guide.md')
// { name: 'guide.md', path: '/docs/guide.md', type: 'file', size: 1234, createdAt: Date, modifiedAt: Date }

Returns: Promise<FileStat>

interface FileStat {
  name: string // File or directory name (basename only)
  path: string // Path relative to the filesystem basePath
  type: 'file' | 'directory'
  size: number
  createdAt: Date
  modifiedAt: Date
  mimeType?: string
}

Optional methods

init()

Initialize the filesystem. Called by workspace.init().

await filesystem.init?.()

destroy()

Clean up resources. Called by workspace.destroy().

await filesystem.destroy?.()

getInfo()

Get filesystem metadata.

const info = await filesystem.getInfo?.()
// { id, name, provider, basePath, readOnly, status, storage? }

Returns: Promise<FilesystemInfo>

interface FilesystemInfo {
  id: string
  name: string
  provider: string
  basePath?: string
  readOnly?: boolean
  status?: string
  storage?: {
    totalBytes?: number
    usedBytes?: number
    availableBytes?: number
  }
}

getInstructions(opts?)

Returns a description of how this filesystem works. Injected into the agent's system message when the workspace is assigned to an agent.

const instructions = filesystem.getInstructions?.()
// 'Local filesystem at "/workspace". Files at workspace path "/foo" are stored at "/workspace/foo" on disk.'

Parameters:

opts.requestContext?:

RequestContext

Forwarded to the instructions function if one was provided in the constructor.

Returns: string

walk(path, options?)

Native recursive tree walk executed by the provider in as few calls as possible. When implemented, the workspace list_files tool uses it instead of issuing one readdir round trip per directory, which matters for remote providers (sandboxes, object stores). If walk throws, tools fall back to the readdir-based walk automatically and log a warning through the workspace logger, since the fallback issues one round trip per directory.

const entries = await filesystem.walk?.('.', { maxDepth: 3 })
// [{ name: 'index.ts', type: 'file', path: 'src/index.ts' }, ...]

Parameters:

path:

string

Directory to walk.

options.maxDepth?:

number

Maximum directory depth to descend (root entries are depth 1).

options.includeHidden?:

boolean

Include entries whose names start with ".". Defaults to false.

Returns: Promise<WalkEntry[]>

interface WalkEntry extends FileEntry {
  path: string // Relative to the walk root, POSIX separators, no leading "./"
}

grep(options)

Native content search executed by the provider (for example with rg or grep inside a sandbox). When implemented, the workspace grep tool delegates to it instead of downloading every file to search host-side. Throw UnsupportedGrepPatternError when a pattern can't run natively so that callers catch it and fall back to the host-side implementation. That fallback is logged at info level; any other error from grep also triggers the fallback but is logged as a warning, since the host-side search reads every candidate file.

const results = await filesystem.grep?.({
  pattern: 'TODO',
  path: '.',
  caseSensitive: true,
  includeHidden: false,
})
// [{ path: 'src/index.ts', matches: [{ line: 3, column: 6, text: '// TODO: fix' }] }]

Parameters:

options.pattern:

string

JavaScript regex source to search for.

options.path:

string

File or directory root to search within.

options.caseSensitive:

boolean

Whether matching is case-sensitive.

options.includeHidden:

boolean

Include hidden files and directories in the search.

options.maxCountPerFile?:

number

Maximum matches per file (like grep -m).

options.maxTotalMatches?:

number

Global cap on total matches across all files.

options.contextLines?:

number

Lines of context to include before and after each match.

Returns: Promise<FilesystemGrepResult[]>

interface FilesystemGrepResult {
  path: string // Relative to the search root, POSIX separators
  matches: FilesystemGrepMatch[]
}

interface FilesystemGrepMatch {
  line: number // 1-based line number
  column: number // 0-based UTF-16 (JS string) index, not a byte offset
  text: string // Full matched line, without trailing newline
  before?: string[] // Context lines before the match
  after?: string[] // Context lines after the match
}

Related

• Workspace Class
• Sandbox Interface