> ## Documentation Index > Fetch the complete documentation index at: https://gofastmcp.com/llms.txt > Use this file to discover all available pages before exploring further. # visibility # `fastmcp.server.transforms.visibility` Visibility transform for marking component visibility state. Each Visibility instance marks components via internal metadata. Multiple visibility transforms can be stacked - later transforms override earlier ones. Final filtering happens at the Provider level. ## Functions ### `is_enabled` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} is_enabled(component: FastMCPComponent) -> bool ``` Check if component is enabled. Returns True if: * No visibility mark exists (default is enabled) * Visibility mark is True Returns False if visibility mark is False. **Args:** * `component`: Component to check. **Returns:** * True if component should be enabled/visible to clients. ### `get_visibility_rules` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} get_visibility_rules(context: Context) -> list[dict[str, Any]] ``` Load visibility rule dicts from session state. ### `save_visibility_rules` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} save_visibility_rules(context: Context, rules: list[dict[str, Any]]) -> None ``` Save visibility rule dicts to session state and send notifications. **Args:** * `context`: The context to save rules for. * `rules`: The visibility rules to save. * `components`: Optional hint about which component types are affected. If None, sends notifications for all types (safe default). If provided, only sends notifications for specified types. ### `create_visibility_transforms` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} create_visibility_transforms(rules: list[dict[str, Any]]) -> list[Visibility] ``` Convert rule dicts to Visibility transforms. ### `get_session_transforms` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} get_session_transforms(context: Context) -> list[Visibility] ``` Get session-specific Visibility transforms from state store. ### `enable_components` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} enable_components(context: Context) -> None ``` Enable components matching criteria for this session only. Session rules override global transforms. Rules accumulate - each call adds a new rule to the session. Later marks override earlier ones (Visibility transform semantics). Sends notifications to this session only: ToolListChangedNotification, ResourceListChangedNotification, and PromptListChangedNotification. **Args:** * `context`: The context for this session. * `names`: Component names or URIs to match. * `keys`: Component keys to match (e.g., {"tool\:my_tool@v1"}). * `version`: Component version spec to match. * `tags`: Tags to match (component must have at least one). * `components`: Component types to match (e.g., {"tool", "prompt"}). * `match_all`: If True, matches all components regardless of other criteria. ### `disable_components` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} disable_components(context: Context) -> None ``` Disable components matching criteria for this session only. Session rules override global transforms. Rules accumulate - each call adds a new rule to the session. Later marks override earlier ones (Visibility transform semantics). Sends notifications to this session only: ToolListChangedNotification, ResourceListChangedNotification, and PromptListChangedNotification. **Args:** * `context`: The context for this session. * `names`: Component names or URIs to match. * `keys`: Component keys to match (e.g., {"tool\:my_tool@v1"}). * `version`: Component version spec to match. * `tags`: Tags to match (component must have at least one). * `components`: Component types to match (e.g., {"tool", "prompt"}). * `match_all`: If True, matches all components regardless of other criteria. ### `reset_visibility` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} reset_visibility(context: Context) -> None ``` Clear all session visibility rules. Use this to reset session visibility back to global defaults. Sends notifications to this session only: ToolListChangedNotification, ResourceListChangedNotification, and PromptListChangedNotification. **Args:** * `context`: The context for this session. ### `apply_session_transforms` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} apply_session_transforms(components: Sequence[ComponentT]) -> Sequence[ComponentT] ``` Apply session-specific visibility transforms to components. This helper applies session-level enable/disable rules by marking components with their visibility state. Session transforms override global transforms due to mark-based semantics (later marks win). **Args:** * `components`: The components to apply session transforms to. **Returns:** * The components with session transforms applied. ## Classes ### `Visibility` Sets visibility state on matching components. Does NOT filter inline - just marks components with visibility state. Later transforms in the chain can override earlier marks. Final filtering happens at the Provider level after all transforms run. **Methods:** #### `list_tools` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} list_tools(self, tools: Sequence[Tool]) -> Sequence[Tool] ``` Mark tools by visibility state. #### `get_tool` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} get_tool(self, name: str, call_next: GetToolNext) -> Tool | None ``` Mark tool if found. #### `list_resources` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} list_resources(self, resources: Sequence[Resource]) -> Sequence[Resource] ``` Mark resources by visibility state. #### `get_resource` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} get_resource(self, uri: str, call_next: GetResourceNext) -> Resource | None ``` Mark resource if found. #### `list_resource_templates` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} list_resource_templates(self, templates: Sequence[ResourceTemplate]) -> Sequence[ResourceTemplate] ``` Mark resource templates by visibility state. #### `get_resource_template` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} get_resource_template(self, uri: str, call_next: GetResourceTemplateNext) -> ResourceTemplate | None ``` Mark resource template if found. #### `list_prompts` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} list_prompts(self, prompts: Sequence[Prompt]) -> Sequence[Prompt] ``` Mark prompts by visibility state. #### `get_prompt` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} get_prompt(self, name: str, call_next: GetPromptNext) -> Prompt | None ``` Mark prompt if found.