Rename Visibility to Enabled, collapse VisibilityRule into the transform,
and move enabled filtering from Provider to Server level so server-level
transforms can override provider-level disables.
Replace _get_all_transforms() with a .transforms property that returns
[*self._transforms, self._visibility]. This cleanly separates user transforms
from visibility filtering while keeping visibility applied last (outermost).
Also:
- AuthMiddleware now uses get_* instead of _get_* for proper component auth
- Remove redundant _is_component_enabled checks (visibility is a transform)
- Delete dead code (get_component method)
- Add versions field to FastMCPMeta
- Replace asserts with NotFoundError in component_service
FastMCP now properly inherits from Provider, eliminating ~200 lines of
duplicated _source_* methods. Key changes:
- get_tool/resource/prompt return None instead of raising NotFoundError
- Visibility filter separated from transforms (applied last)
- Nested server middleware runs on both list and execution operations
- Resource auth failure doesn't fall back to templates
- AggregateProvider kept as user-facing utility class
* Consolidate tool transformation logic into TransformingProvider
Tool transformations were previously scattered across LocalProvider,
ProxyProvider, and MCPConfig. This consolidates all transformation
logic into TransformingProvider via with_transforms(tool_transforms={...}).
- Add tool_transforms parameter to TransformingProvider
- Add tool_transforms to Provider.with_transforms()
- Remove transformation storage from LocalProvider and ProxyProvider
- Remove add_tool_transformation() and remove_tool_transformation() from FastMCP
- Add tool_transforms parameter to factory methods (from_openapi, from_fastapi, create_proxy)
- Update tests to use new patterns
* Fix: reject tool lookups by pre-transform name
* Add collision validation for tool_transforms and fix docstring examples
- Validate duplicate target names in tool_transforms raise ValueError
- Fix docstring examples to use arguments/ArgTransformConfig (not args/ArgTransform)
- Add test for collision validation
* Add server-level tool transform APIs and fix task registration
- Add AggregateProvider to present multiple providers as one
- Add _get_root_provider() to apply server-level transforms uniformly
- Fix _docket_lifespan to use root provider (ensures renamed tools
register with correct keys for background execution)
- Add tool_transforms kwarg to __init__ (non-deprecated)
- Add add_tool_transform(), remove_tool_transform(), tool_transforms property
- Deprecate old API names (tool_transformations, add_tool_transformation, etc.)
- Update tests to use new API
* Add graceful degradation for provider errors in AggregateProvider
* Match original behavior: parallel queries with DEBUG logging
* Refactor transforms to middleware-style call_next pattern
Replaces the ad-hoc transformation system with a unified Transform
abstraction using the same call_next pattern as server middleware.
Key changes:
- New src/fastmcp/server/transforms/ module with Transform base class
- Namespace, ToolTransform, Visibility all implement the same interface
- Transforms compose via functools.partial chain building
- Visibility is now just the first transform in provider._transforms
- Server-level transforms apply after provider aggregation
- Task registration now applies full transform chain
Removes TransformingProvider, _BoundTransform, ComponentSource protocol.
User-facing API unchanged: mount(), add_transform(), enable/disable all
work as before.
* Add comprehensive transforms and visibility documentation
New docs/servers/providers/transforms.mdx covering:
- Mental model for middleware-style transform pattern
- Built-in transforms (Namespace, ToolTransform)
- Server vs provider-level transforms and ordering
- Tool modification (immediate vs deferred)
- Custom transform creation
New docs/servers/visibility.mdx covering:
- Enable/disable API for runtime visibility control
- Keys and tags for targeting components
- Allowlist mode with only=True
- Server vs provider visibility layering
Updates existing docs to reference new pages and simplifies
redundant content. Visibility is documented as a user feature,
not as an implementation detail.
* Restructure transforms docs and delete tool-transformation pattern
* Cleanup: simplify get_tasks and remove unused Provider.get_component
* Update loq
* Update loq limits and add loq note to AGENTS.md
* Deprecate add_tool_transformation and tool_transformations param
* Address PR review feedback: remove redundant imports, fix path reference
* Add missing imports to code examples in v3-features.mdx
* Refactor FastMCPProxy into ProxyProvider
Move proxy functionality from custom manager classes to the Provider pattern:
- Create ProxyProvider that implements the Provider interface
- Move all proxy code to src/fastmcp/server/providers/proxy.py
- Keep FastMCPProxy as a convenience wrapper using ProxyProvider
- Add deprecation warning when importing from old location
- Convert handler classmethods to module-level functions
- Remove redundant get_* methods (base class defaults work)
* Remove unused Components class, simplify TaskComponents()
* Replace type: ignore[attr-defined] with isinstance assertions in tests
* Fix isinstance assertions in failing tests
- Fix enum test to check for ResponseEnum instead of str
- Fix binary resource test to check for BlobResourceContents instead of TextResourceContents
- Fix Root type tests to check attributes directly instead of isinstance checks
* Fix type errors without using type: ignore
- Remove execution methods from TransformingProvider (only handles transformations)
- Add execution methods to base Provider class with default implementations
- Fix type narrowing in tests using cast() instead of type: ignore
- Fix PromptResult type handling in prompt render tests
- Fix type narrowing in middleware test for arguments and structured_content
* Add test_custom_subclass_tasks.py
* Refactor provider execution: delegate to middleware via wrapper components
- Remove execution methods (call_tool, read_resource, etc.) from Provider base
- Add FastMCPProvider* wrapper classes that delegate to child server middleware
- Move task routing to Tool._run() using contextvars (_task_metadata, _tool_call_key)
- Add convert_to_tool_result(result, output_schema) utility for Docket results
- Add convert_to_prompt_result() utility for prompt task results
- Pass namespaced key via add_to_docket(name=) for mounted tool lookup
* Standardize add_to_docket() with fn_key/task_key parameters
All components now use explicit fn_key (function lookup) and task_key
(result storage) parameters instead of relying on implicit key handling.
This fixes mounted component task execution where the MCP-visible key
differs from the Docket-registered function name.
* Add middleware chain tests for three-level mount hierarchy
Tests verify middleware runs at parent, child, and grandchild levels
for tools, resources, prompts, and resource templates.
* WIP: Provider refactor - unified submit_to_docket, template _read() in progress
Work in progress on refactoring execution to use component _read()/_run()/_render() methods.
Template background tasks not yet working - needs fix for Docket key lookup.
* Fix conversion functions to take full component for attribute access
Pass Tool/Prompt/Resource/Template to conversion functions instead of
individual attributes, ensuring access to serializer, output_schema,
mime_type, etc. Also fixes mixed-content output schema validation.
* Refactor: unified convert_result() methods and check_background_task helper
- Add convert_result() instance methods to all component types (Tool, Prompt, Resource, ResourceTemplate)
- Extract duplicated task routing logic into check_background_task() helper
- Fix type annotations on FastMCPProviderResource.read() and FastMCPProviderPrompt.render()
- Update protocol.py to use component.convert_result() uniformly
* Update tests to use namespace= instead of deprecated prefix= parameter
* Refactor MountedProvider into FastMCPProvider + TransformingProvider
Split the monolithic MountedProvider into two focused components:
- FastMCPProvider: wraps a FastMCP server as a provider
- TransformingProvider: applies namespace/rename transformations to any provider
Add with_transforms() method to Provider base class for fluent API.
Rename mount() prefix parameter to namespace (deprecate prefix).
* Reuse compiled URI_PATTERN in deprecated import_server
* Simplify .key as computed property
Keep .key as the standard lookup interface for all components but
implement it as a computed property instead of a stored field.
- Remove _key private attribute and custom model_copy(key=...)
- .key returns .name for tools/prompts, str(.uri) for resources,
.uri_template for templates
- Use .key universally for component lookups in managers
- MountedProvider: prefix URIs only for resources/templates, not names
- Docket registration: tools/prompts use .key, resources use .name
(matches fn.__name__ for function lookup)
* Simplify .key as computed property
Keep .key as the standard lookup interface for all components but
implement it as a computed property instead of a stored field.
- Remove _key private attribute and custom model_copy(key=...)
- .key returns .name for tools/prompts, str(.uri) for resources,
.uri_template for templates
- Use .key universally for component lookups and Docket registration
- MountedProvider: prefix URIs only for resources/templates, not names
- Add _backend_* fields to proxy classes to preserve original identifiers
for backend calls when prefixed via import_server
* Standardize .key as computed property
- .key is now a read-only computed property:
- Tools/Prompts: returns .name
- Resources: returns str(.uri)
- Templates: returns .uri_template
- Prefixing uses model_copy(update={...}) to change underlying field
- Resource/template names are NOT prefixed, only URIs
- Move import_server tests to tests/deprecated/
* Simplify Provider interface and consolidate docket registration
- Remove get_http_routes from Provider (unused)
- Remove ProviderLifespanConfig, _base_lifespan, _register_tasks
- Remove supports_tasks flag from Provider.__init__
- Consolidate all docket registration in server._docket_lifespan()
- Simplify lifespan() to take no parameters
- Move MountedProvider to separate module
* Fix control flow in ComponentService resource methods
* Move providers to server/providers
* Ensure MountedProvider get_* methods go through middleware
* Fix get_resource to only return concrete resources
Reverts template-checking in get_resource that broke task execution.
Tasks need access to the original template, not instantiated resources.
* Move prefix utilities into mounted.py, deprecate import_server
- Add resource prefix functions (add/remove/has_resource_prefix) to mounted.py
- Deprecate import_server with warning to use mount() instead
- Add tool_names uniqueness validation in MountedProvider
* Fix provider iteration order and remove dead _is_mounted flag
- Remove unused _is_mounted flag (MountedProvider.lifespan() calls _lifespan
not _lifespan_manager, so the flag was never checked)
- Fix provider iteration: change reversed() to forward order in execution
methods (_call_tool, _read_resource_middleware, _get_prompt_content_middleware)
to match documented "first non-None wins" semantics
- Fix ComponentService to handle prefix-less mounted servers using
_strip_tool_prefix()/_strip_resource_prefix() methods
- Update conflict resolution tests to expect first-registered provider wins
- Add regression tests for Docket behavior and prefix-less ComponentService
* Add TaskComponents type and exception handling for provider task registration
- Create TaskComponents dataclass with FunctionTool/FunctionResource/etc. types
for proper typing of get_tasks() return value
- Add try/except wrapper around provider.get_tasks() in _docket_lifespan for
consistent error handling (warn + continue or raise based on settings)
- Remove type: ignore comments from server.py task registration loop
Tools, resources, and prompts from servers mounted more than 2 levels
deep failed to invoke even though they were correctly listed.
The bug was in the routing methods which used manager methods that only
search locally, not through nested mounted servers. Changed to use
server-level methods that search recursively.
Fixes#2583
Docket provides background task execution and is now always available
for all FastMCP servers. Only `enable_tasks` remains to control the
SEP-1686 task protocol support.
Changes:
- Remove `enable_docket` setting and related validation
- Docket/Worker lifecycle is always active in server lifespan
- CurrentDocket and CurrentWorker dependencies work without config
- Add server readiness signaling via `_started` event
- Fix test timing issues with proper port probing
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
* Initialize 2.14 deprecation removal branch
* Remove deprecated FASTMCP_SERVER_ environment variable prefix (#2330)
* Remove deprecated Context.get_http_request method (#2332)
* Remove fastmcp.Image top-level import (deprecated 2.8.1) (#2334)
* Remove test warnings (#2331)
* Create new branch and fix issue
* Remove deprecated client parameter from FastMCPProxy (#2333)
* Remove deprecated run_streamable_http_async method (#2338)
* Remove deprecated sse_app method (#2337)
* Remove deprecated run_sse_async method (#2335)
* Remove deprecated run_sse_async method
* Update CLI and tests to use run_http_async(transport="sse")
- Change CLI to call run_http_async with transport="sse" instead of run_sse_async
- Update test to mock run_http_async with create=True for v1 servers
* Revert CLI changes - v1 servers do have run_sse_async
- Keep CLI calling run_sse_async() for v1 compatibility
- Update test to mock run_sse_async (which exists on v1)
* Remove unnecessary type ignore for run_sse_async
Method exists on v1 FastMCP class, no type error
* Remove unused imports after test deletion
* Remove deprecated streamable_http_app method (#2336)
* Remove deprecated dependencies parameter from FastMCP constructor (#2340)
* Remove output_schema=False support (deprecated 2.11.4) (#2339)
* Remove deprecated client parameter from FastMCPProxy (#2333)
* Delete deprecated test_output_schema_false.py
Tests functionality that has been removed
* Remove deprecated BearerAuthProvider module (#2341)
* Remove resource_prefix_format="protocol" support (deprecated 2.4.0) (#2342)
* Remove resource_prefix_format="protocol" support (fixes#2195)
Removes deprecated protocol format (prefix+resource://path) and keeps only
path format (resource://prefix/path). Since only one format remains:
- Removed resource_prefix_format from settings, FastMCP.__init__, and helpers
- Simplified add_resource_prefix, remove_resource_prefix, has_resource_prefix
- Removed MountedServer.resource_prefix_format field
- Deleted tests for protocol format
All resource prefixes now use path format exclusively.
* Clean up resource_prefix_format references
- Remove from test files
- Update documentation to remove protocol format section
- Move custom HTTP routes note to mounting section
- Remove resource_prefix_format from settings docs
* Use inline version note instead of badge for prefix format
* Remove obsolete test functions and update docs
- Delete test functions that no longer assert anything
- Remove proxy.mdx reference to deleted prefix format section
* Format error messages per ruff
* Remove from_client classmethod (deprecated 2.8.0) (#2343)
* Remove deprecated from_client classmethod (fixes#2192)
* Remove unused Client import
* Remove add_resource_fn method (deprecated 2.7.0) (#2345)
* Update SDK
* Add missing imports for exclude_args deprecation warning
Because the server now validates inputs, its no longer viable to provide a JSON string where e.g. an array is expected, so we can entirely remove FastMCP's "legacy json parsing" support from 1.x.
This is a breaking change (for legacy opt-in behavior)
