mcpapps

type CSPSources struct {
	// Resource feeds script-src, style-src, img-src, font-src, and media-src.
	Resource []string

	// Connect feeds connect-src and is what `can connect` declares. The other
	// three families have no guardfile verb yet.
	Connect []string

	// Frame feeds frame-src, and BaseURI feeds base-uri.
	Frame   []string
	BaseURI []string

	// Report names a collector path for violation reports. It is umbra's
	// addition rather than the spec's, and it grants nothing.
	Report string
}

type DownloadItem struct {
	URI      string
	MIMEType string

	// Raw is the item as the view sent it, so a handler saving inline bytes
	// reads them without this package modelling every content shape.
	Raw json.RawMessage
}

type Frame struct {
	JSONRPC string          `json:"jsonrpc"`
	ID      json.RawMessage `json:"id,omitempty"`
	Method  string          `json:"method,omitempty"`
	Params  json.RawMessage `json:"params,omitempty"`
}

type Host struct {
	// Info identifies this host to the view during ui/initialize.
	Info Implementation

	// Context is sent as `hostContext`. Omitting it entirely leaves the view's
	// SDK never-ready, so Handle substitutes a minimal one.
	Context HostContext

	// Instantiating is the tools/call result that created this view, pushed as
	// ui/notifications/tool-result when the view says it is initialized.
	Instantiating any

	// Session is the upstream a permitted call reaches. A nil Session refuses
	// every proxied frame rather than dropping it.
	Session Session

	// Policy gates every view-initiated call. A nil Policy permits none, which
	// is what makes an undeclared widget inert.
	Policy Policy

	// Emit posts an unsolicited frame to the view. The SDK calls it from its own
	// goroutine, so it must be safe concurrently. nil drops them.
	Emit func(Reply)

	// OpenLink opens a URL the policy permitted. nil leaves `openLinks`
	// undeclared, so a view learns rather than asking for what never happens.
	OpenLink func(ctx context.Context, url string) error

	// SaveFile hands permitted contents to the viewer. nil leaves
	// `downloadFile` undeclared, for the same reason.
	SaveFile func(ctx context.Context, items []DownloadItem) error
	// contains filtered or unexported fields
}

type HostContext map[string]any

type Implementation struct {
	Name    string `json:"name"`
	Version string `json:"version,omitempty"`
}

type Policy interface {
	// Tools is the surface the view may see and call: deny by absence, the
	// same rule the CLI leaves follow. See docs/mcpapps.md.
	Tools() []mcpclient.Tool

	// CheckToolCall reports why this view-initiated call is refused, or nil. It
	// runs after Tools membership, so it guards arguments rather than names.
	CheckToolCall(tool string, args map[string]any) error

	// CheckResourceRead reports why this view-initiated read is refused, or nil.
	CheckResourceRead(uri string) error

	// CheckOpenLink reports why opening this URL for the view is refused, or
	// nil. Opening a URL an untrusted view chose is its own grant.
	CheckOpenLink(url string) error

	// CheckSaveFile reports why handing this resource to the viewer to save is
	// refused, or nil. It gates the URI of a link and of an inline resource.
	CheckSaveFile(uri string) error
}

type RPCError struct {
	Code    int    `json:"code"`
	Message string `json:"message"`
	Data    any    `json:"data,omitempty"`
}

type Reply struct {
	// contains filtered or unexported fields
}

type Session interface {
	Call(ctx context.Context, c mcpclient.Call) (mcpclient.Result, error)
	ReadResource(ctx context.Context, uri string) (*mcp.ReadResourceResult, error)
	ListResources(ctx context.Context) ([]mcpclient.Resource, error)
}