Fix app tool routing: visibility check and middleware propagation#3591
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Fix app tool routing: visibility check and middleware propagation#3591
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- get_app_tool now checks that tools have "app" in their visibility, preventing model-only @app.ui() tools from being callable via app routing - FastMCPProviderTool._run passes app_name to child server so app tool routing works through mounted servers (child middleware runs correctly) - add_tool sets default visibility=["app"] when not specified
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| raw_tool = await self.server.get_app_tool(app_name, tool_name) | ||
| if raw_tool is None: | ||
| return None | ||
| return FastMCPProviderTool.wrap(self.server, raw_tool) |
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Tool.run() for mounted app lookups
FastMCPProvider.get_app_tool() now wraps the child tool before returning it, but FastMCPProviderTool.run() still delegates with only self._original_name. In a mounted app behind transforms (for example outer.mount(inner, namespace="inner") with inner.add_provider(app, namespace="app")), await outer.get_app_tool("deep", "hidden") now returns a wrapper whose run({...}) raises NotFoundError, because the child server needs app_name to bypass its transforms. Before this change get_app_tool() returned the raw tool, so the public Tool returned by this API remained directly callable.
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Co-authored-by: Claude Opus 4.6 <[email protected]> Co-authored-by: Jeremiah Lowin <[email protected]> Co-authored-by: Marvin Context Protocol <41898282+Marvin Context [email protected]> Co-authored-by: voidborne-d <[email protected]> Co-authored-by: marvin-context-protocol[bot] <225465937+marvin-context-protocol[bot]@users.noreply.github.com> Co-authored-by: Claude <[email protected]> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com> Co-authored-by: d 🔹 <[email protected]> Co-authored-by: Jeremiah Lowin <[email protected]> Co-authored-by: nightcityblade <[email protected]> Co-authored-by: Claude Opus 4.6 (1M context) <[email protected]> Co-authored-by: Claude Sonnet 4.6 <[email protected]> Co-authored-by: Bill Easton <[email protected]> Co-authored-by: Sumanshu Nankana <[email protected]> Co-authored-by: Eric Robinson <[email protected]> Co-authored-by: Martim Santos <[email protected]> Co-authored-by: d 🔹 <[email protected]> Co-authored-by: Matthieu B <[email protected]> Co-authored-by: Sascha Buehrle <[email protected]> Co-authored-by: Hakancan <[email protected]> Co-authored-by: nightcityblade <[email protected]> Co-authored-by: Matt Hallowell <[email protected]> Co-authored-by: nate nowack <[email protected]> Co-authored-by: Bill Easton <[email protected]> Co-authored-by: Marcus Shu <[email protected]> Co-authored-by: Rushabh Doshi <[email protected]> Co-authored-by: AIKAWA Shigechika <[email protected]> Co-authored-by: Jeremy Simon <[email protected]> Co-authored-by: Miguel Miranda Dias <[email protected]> Co-authored-by: Anthony James Padavano <[email protected]> Co-authored-by: Mostafa Kamal <[email protected]> Fix auto-close MRE script posting comment without closing (#3386) Fix WorkOS token scope verification bypass 🤖 Generated with Codex (#3407) Fix initialize McpError fallthrough 🤖 Generated with Codex (#3413) Fix transform arg collisions with passthrough params (#3431) Fix get_* returning None when latest version is disabled (#3439) Fix get_* returning None when latest version is disabled (#3421) Fix server lifespan overlap teardown (#3415) Fix $ref output schema object detection regression (#3420) resolved annotations (#3429) Fix async partial callables rejected by iscoroutinefunction (#3438) Fix async partial callables rejected by iscoroutinefunction (#3423) fix: add version to components (#3458) fix: use intent-based flag for OIDC scope patch in load_access_token (#3465) Fixes #3461 fix: normalize Google scope shorthands and surface valid_scopes (#3477) fix: resolve ty 0.0.23 type-checking errors and bump pin (#3481) fix: shield lifespan teardown from cancellation (#3480) fix: forward custom_route endpoints from mounted servers (#3462) fix updates _get_additional_http_routes() to traverse providers, Fixes #3457 fix: remove hardcoded version from CLI help text (#3456) fix: monty 0.0.8 compatibility, drop external_functions from constructor (#3468) fix: task test teardown hanging 5s per test (#3499) Closes #3498 fix: validate workspace path is a directory before cursor install (#3440) Fixes #3426 fix: handle re.error from malformed URI templates in build_regex (#3501) fix: reject empty/OIDC-only required_scopes in AzureProvider (#3503) fix: restrict $ref resolution to local refs only (SSRF/LFI) (#3502) fix warnings and timeouts (#3504) close upgrade check issue when build passes (#3505) Closes #3484 fix: URL-encode path params to prevent SSRF/path traversal (GHSA-vv7q-7jx5-f767) (#3507) fix: prevent path traversal in skill download (#3493) fix: prefer IdP-granted scopes over client-requested scopes in OAuthProxy (#3492) fix: remove unrelated transform and http.py changes from PR scope fix: remove forced follow_redirects from httpx_client_factory calls (#3496) fix: stop passing follow_redirects to httpx_client_factory fix: restore follow_redirects=True for custom httpx client factories Closes #3509 fix: CSRF double-submit cookie check in consent flow (#3519) fix: validate server names in install commands (#3522) fix: use raw strings for regex in pytest.raises match (#3523) fix: reject refresh tokens used as Bearer access tokens (#3524) fix: route ResourcesAsTools/PromptsAsTools through server middleware (#3495) fix: resolve Pyright "Module is not callable" on @tool, @resource, @prompt decorators (#3540) fix: filter warnings by message in KEY_PREFIX test (#3549) fix: suppress output schema for ToolResult subclass annotations (#3548) fix: increase sleep duration in proxy cache tests (#3567) fix: store absolute token expiry to prevent stale expires_in on reload (#3572) fix: preserve tool properties named 'title' during schema compression (#3582) Fix loopback redirect URI port matching per RFC 8252 §7.3 (#3589) Fix app tool routing: visibility check and middleware propagation (#3591) Fix query parameter serialization to respect OpenAPI explode/style settings (#3595) Fix dev apps form: union types, textarea support, JSON parsing (#3597) fix(google): replace deprecated /oauth2/v1/tokeninfo with /oauth2/v3/userinfo (#3603) fix: resolve EntraOBOToken dependency injection through MultiAuth (#3609) fix(docs): correct misleading stateless_http header (#3622) fix: filesystem provider import machinery (#3626) Closes #3625 (issues 2, 3, 6) fix: recover StdioTransport after subprocess exits (#3630) fix(server): preserve mounted tool task metadata (#3632) fix: scope deprecation warning filter to FastMCPDeprecationWarning (#3649) fix imports, add PrefabAppConfig (#3650) fix: resolve CurrentFastMCP/ctx.fastmcp to child server in mounted background tasks (#3651) Fix blocking docs issues: chart imports, Select API, Rx consistency (#3652) closed by default (#3657) Fix prompt caching middleware missing wrap/unwrap round-trip (#3666) fix: serialize object query params per OpenAPI style/explode rules (#3662) Fixes #2857 fix: HTTP request headers not accessible in background task workers (#3631) fix: restore HTTP headers in worker execution path for background tasks (#3681) fix: strip discriminator after dereferencing schemas (#3682) fix: remove stale ty:ignore directives for ty 0.0.26 (#3684) Fix docs gaps in app provider pages (#3690) fix: dev apps log panel UX improvements (#3698) fix dev server empty string args (#3700)
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Addresses two issues from #3587 review comments:
Visibility check:
get_app_toolnow only returns tools that have"app"in theirmeta.ui.visibility. Previously it would return@app.ui()tools (which are model-only,visibility=["model"]), letting a UI invoke entry-point tools it shouldn't be able to call.Middleware propagation: When an app tool is found through a mounted server (
FastMCPProvider), the tool's_runmethod now passesapp_nameto the child server'scall_tool. Without this, the child server tried normal resolution (which fails because transforms block the untransformed name).