72 skills published by facebook across 12 repositories. Together they weigh 292 102 tokens — that is what loading all of them at once would cost you in context.
72 skills 292 102 tokens total
>- Best practices for writing idiomatic Relay code. ALWAYS use this skill when writing or modifying React components that use Relay for data fetching. Covers fragments, queries, mutations, pagination, and common anti-patterns. Use when you see `useFragment`, `useLazyLoadQuery`, `usePreloadedQuery`, `useMutation`, `usePaginationFragment`, `graphql` template literals, `react-relay` imports, or `__generated__/*.graphql` files. Also use when asked to explain Relay concepts, debug Relay issues, or review Relay code.
Write and run markdown-driven e2e tests for Relay. Covers fixture format, server/client code patterns, interaction DSL, snapshots, and running tests.
>- Performance best practices for Relay applications. Use when optimizing data fetching, reducing re-renders, configuring caching, or improving time to first meaningful paint. Covers query placement, @defer, pagination, fetch policies, garbage collection, fragment granularity, and server-side filtering. Companion to the relay-best-practices skill which covers correctness and architecture.
> Guide for adding a new IR instruction to the Hermes compiler. Use when the user asks to add, create, or define a new IR instruction (Inst/Instruction) in the Hermes intermediate representation. Covers all required files and the patterns for each.
> This skill should be used when the user wants to analyze hermesvm binary size changes across a range of commits. Use when the user mentions "binary size", "size analysis", "size regression", "size increase", or asks to measure how commits affect the hermesvm library size.
> Rules for writing and reviewing GC-safe C++ code in the Hermes VM runtime. Use when writing, modifying, or reviewing C++ runtime VM code that uses internal Hermes VM APIs (as opposed to code using JSI). This includes working with GC-managed types (HermesValue, Handle, PinnedValue, JSObject, StringPrimitive, etc.), Locals, GCScope, PseudoHandle, CallResult, or any function with _RJS suffix. Typically in lib/VM/, include/hermes/VM/, API/hermes/, or API/napi/.
> Guide for adding new JSI functionality to the JavaScript Interface (JSI) layer. Use when the user asks to add, create, or implement new methods or features in the JSI Runtime interface. Covers all required files across JSI core, Hermes implementation, and SynthTrace replay support.
Use when needing to reorder, split, drop, or amend git commits that are not the top commit, without interactive editor access. Covers programmatic rebase via GIT_SEQUENCE_EDITOR, commit splitting with automated hunk selection, and metadata changes (author, message, dates) on any commit in a range.
Use when you need to understand the Pyre or Pysa codebase architecture, find where specific functionality is implemented, or navigate the source directory structure. Use when working on OCaml code, debugging type checking or taint analysis issues, or exploring the codebase.
Use when creating commits or diffs to apply the correct title prefix, reviewer, and test plan based on the area of the codebase being changed.
Use when debugging a Pysa false negative (missing taint issue), comparing two Pysa output directories, or finding where taint flow is lost.
Use when running, debugging, updating, or creating Pysa end-to-end integration tests. Use when taint analysis tests fail, when expected output files need updating, or when working with .models, .cg, .hofcg, .overrides files under `source/interprocedural_analyses/taint/test/integration`.
Use when reading, writing, or debugging Pysa JSON model output (.models files). Use when working with taint models that describe sources, sinks, TITO, sanitizers, or issues in JSON format.
> This guide explains how to create new EdenAPI/SLAPI endpoints, covering both streaming and non-streaming patterns.
Triage systemd-managed EdenFS issues on Linux devservers and OnDemands. Use when investigating EdenFS service failures, unexpected restarts, systemctl errors, edenfs_upgrade/edenfs_restarter problems, or when a user reports EdenFS is down on a systemd-enabled host. Also use when someone asks how systemd-managed EdenFS works, how to monitor it, or how to check its health. Use when asked to build a timeline of EdenFS lifecycle events, show edenfs restart history, or understand how edenfs reached its current state. Trigger on mentions of edenfs systemd, edenfs@ service, edenfs_upgrade timer, edenfs auto-restart, eden status --debug, systemctl edenfs, edenfs lifecycle management, edenfs timeline, edenfs restart history, or "what happened to edenfs".
> Load FIRST before searching code in eden/. Contains component-to-file maps, key type names, and architecture diagrams for EdenFS, Sapling, and Mononoke. Tells you exactly which files to read for any task. References contain per-component quick reference tables.
> Add or review structured error logging in EdenFS daemon (C++) — the ErrorLogger / EdenErrorInfo system that feeds the edenfs_errors table. Use when exception_wrapper / .thenError), instrumenting a failure path, or debugging a wrong stack trace or wrong component. Covers throw-site trace rules, component choice, errorType, noise filtering, gating, and testing.
Create a Mononoke server-side hook with 3-diff split (tests, wiring, implementation), unit tests, and integration tests
> Port a PyTorch model to use pyrefly's tensor shape type system (Tensor[[B, C, H, W]], Int[T]). Use this skill whenever the user wants to add shape annotations to a PyTorch model, type a model with tensor dimensions, port a model to use shape tracking, or annotate model forward methods with tensor shapes. Also use when the user mentions tensor shape ports, Int types for PyTorch, or pyrefly shape checking on a model file. Invoke BEFORE starting any model port — the skill's gated workflow prevents common failure modes.
Use when Pyrefly computes a wrong tensor shape (or is missing one that can't be expressed in a stub signature) and you need to add or fix a shape-DSL rule. Requires a Pyrefly checkout (fbsource or a clone); not usable from a pip/site-packages install.
Guide users through writing their first Buck2 rule to learn fundamental concepts including rules, actions, targets, configurations, analysis, and select(). Use this skill when users want to learn Buck2 basics hands-on or need help understanding rule writing.
Design patterns and requirements for OpenZL codecs (located under `src/openzl/codecs/`). **USE AUOMATICALLY** when creating, modifying, or reviewing codecs in OpenZL.
Design documentation for the OpenZL component registry located under tests/registry. **USE AUTOMATICALLY** whenever editing files under tests/registry/.
How to mint real OpenZL frames and chunks for GPU decoder tests using the contrib/gpu/testkit utilities (frame_factory, multichunk_frame, frame_verifier), and how to extract a codec's encoded streams via reflection for differential GPU decode. USE when writing or reviewing GPU-decoder tests that need OpenZL-encoded fixtures.
Use when creating benchmark scenarios for new openzl codec nodes in unitBench - adding kernel-level encode/decode benchmarks or graph-level compress/decompress benchmarks for codecs like bitsplit, delta, transpose, entropy, etc.
Debug FBOSS AgentHwTest failures - build, run, analyze logs, crash debug, vendor diag shell, hypothesis-driven debugging. Use when running sai_agent_hw_test or multi_switch_agent_hw_test and investigating test failures.
FBOSS coding standards and patterns. Auto-loaded when writing code in fboss/ to catch architecture violations, SAI/SDK misuse, thrift_cow pitfalls, platform config errors, and testing gaps. For explicit multi-reviewer review, use /fboss-review instead.
Comprehensive FBOSS code review with 11 parallel reviewers (5 generic + 6 FBOSS-specific). Covers reliability, engineering, code quality, silent failures, agent architecture, SAI/SDK, FSDB/thrift_cow, platform/config, testing, and cross-cutting design. Self-contained alternative to /review-diff for FBOSS diffs. Findings shown to user only, never auto-posted.
Stream, video frames, photo capture, resolution/frame rate configuration
Swift patterns, async/await, naming conventions, key types for DAT SDK iOS development
Common issues, Developer Mode, version compatibility, state machine diagnosis
Display capability setup, display-capable device selection, UI DSL, icons, buttons, images, and video playback
SDK setup, Swift Package Manager integration, Info.plist configuration, and first connection to Meta glasses
Use this whenever debugging an iOS DAT app with local DAT Inspector MCP tools, live device events, Meta AI app/device boundary issues, permissions, registration, sessions, streaming, callbacks, or user reports that the app cannot communicate with glasses.
MockDeviceKit for testing without physical glasses hardware
App registration with Meta AI, camera permission flows
Building a complete DAT app with camera streaming and photo capture
Device session states, pause/resume, availability monitoring
Find and click a target object in XR. Use when testing UI interactions, clicking buttons, or verifying interactable elements work correctly.
Debug continuous behavior in WebXR scenes — physics, animations, collisions, game loops, or any real-time interaction that happens too fast for an agent to observe. Uses ECS pause/step/snapshot/diff to freeze time and inspect state frame by frame.
Guide for implementing depth sensing and occlusion in IWSDK projects. Use when adding depth-based occlusion to hide virtual objects behind real-world surfaces, configuring DepthSensingSystem, choosing occlusion modes, or troubleshooting objects that disappear or fail to occlude.
Grab an object in the WebXR scene using emulated controllers. Use when the user wants to pick up, move, or test grabbing an object. Supports OneHandGrabbable and TwoHandsGrabbable components which use proximity-based grip (squeeze button), not trigger.
Migrate an existing IWSDK 0.4.x application to IWSDK 0.5.0. Use when upgrading across the 0.5 boundary, replacing Meta Spatial Editor or GLXF, removing retired Vite plugins, moving UIKitML to runtime-loaded assets, adopting native scene JSON, or resolving 0.5 migration errors.
Guide for implementing physics in IWSDK projects. Use when adding physics simulation, configuring rigid bodies, collision shapes, applying forces, creating grabbable physics objects, or troubleshooting physics behavior.
IWSDK experience pipeline and planning guide. Use when building a new IWSDK app/game end-to-end, planning new IWSDK features, designing systems/components, reviewing IWSDK code architecture, or when the user asks about IWSDK patterns, ECS design, signals, or reactive programming. Runs a phased ideation → design → grounding → architecture → build → verify → ship pipeline, orchestrating sub-agents per phase where the harness supports them.
Ray-based interactions in the WebXR scene — click objects, press UI buttons, or distance-grab with DistanceGrabbable. Use when the user wants to point at and interact with something at a distance, click a UI button, or test ray-based selection.
Compose editable static IWSDK scenes from text, images, or hybrid references using a shared application asset manifest, v1 scene JSON, modular scene files, and the managed editor's validation and rendering tools. Use for 3D environments, props, architecture, staged scenes, procedural Three.js assets, custom PBR or shader materials, glTF assets, prefabs, patterns, lighting, camera matching, or visual review.
Create, place, preview, debug, and connect manifest-backed IWSDK UIKitML assets. Use for spatial panels, browser HUDs, UIKitML layout, fonts, editor previews, or runtime element behavior.
Create, place, preview, debug, and connect manifest-backed IWSDK UIKitML assets. Use for spatial panels, browser HUDs, UIKitML layout, fonts, editor previews, or runtime element behavior.
Parallel test orchestrator. Runs all 9 test suites concurrently via Task sub-agents and the iwsdk CLI. Handles build, example setup, dev servers, agent launch, polling, retries, and result aggregation.
Test audio system (AudioSource loading, playback state, stop, spatial audio) against the audio example using the iwsdk CLI.
Test ECS core functionality (system registration, components, Transform sync, pause/step/resume, system toggle, entity discovery, snapshots) against the poke example using the iwsdk CLI.
Test environment system (authored DomeGradient and IBLGradient, component schemas) against the poke example using the iwsdk CLI.
Test grab system (distance grab, one-hand grab, two-hand grab) against the grab example using the iwsdk CLI.
Test XR interactions (ray, poke/touch, dual-mode, audio, UI panel) against the poke example using the iwsdk CLI.
Test level system (LevelRoot, LevelTag, authored environment, scene hierarchy) against the poke example using the iwsdk CLI.
Test locomotion system (slide, snap turn, teleport, jump) against the locomotion example using the iwsdk CLI.
Test Havok physics system (gravity, rigid bodies, static vs dynamic) against the physics example using the iwsdk CLI.
Test UIKitML asset and ScreenSpace UI behavior against the poke example using the iwsdk CLI.
Test XR session lifecycle and mode transitions. Use when verifying XR enter/exit behavior, testing mode-dependent features, or debugging session state issues.
Session and Stream capability setup, video frames, photo capture, resolution and frame rate configuration
Kotlin patterns, DatResult, session and capability conventions for DAT SDK Android development
Common issues, Developer Mode, version compatibility, and session and stream diagnosis
Display capability setup, display-capable device selection, UI DSL, icons, buttons, images, and video playback
SDK setup, Gradle integration, AndroidManifest configuration, and first connection to Meta glasses
Use this whenever debugging an Android DAT app with local DAT Inspector MCP tools, live device events, Meta AI app/device boundary issues, permissions, registration, sessions, streaming, or user reports that the app cannot communicate with glasses.
MockDeviceKit for testing without physical glasses hardware
App registration with Meta AI and device permission flows
Building a complete DAT app with session creation, camera streaming, and photo capture
Session state, stream state, pause and resume behavior, and device availability monitoring
IWSDK experience pipeline and planning guide. Use when building a new IWSDK app/game end-to-end, planning new IWSDK features, designing systems/components, reviewing IWSDK code architecture, or when the user asks about IWSDK patterns, ECS design, signals, or reactive programming. Runs a phased ideation → design → grounding → architecture → build → verify → ship pipeline, orchestrating sub-agents per phase where the harness supports them.