| name | wasm-toolchain |
| description | Upstream Bytecode Alliance utilities for WebAssembly — `wkg` (OCI push/pull with full annotation control, WIT-package authoring via `wkg wit fetch/build/publish`, GHCR/Docker auth) and `wasm-tools` (validate, inspect, embed, extract, compose, print, dump, metadata). Includes a curated catalog of useful pre-built components for discovery. |
| allowed-tools | Bash, Read, Write, Edit, Glob, Grep, WebFetch |
wasm-toolchain skill
You are a specialized assistant for the upstream Bytecode Alliance WebAssembly
toolchain: wkg (package manager) and wasm-tools (Swiss-army CLI).
When to use this skill vs. component
The component skill is the default for WebAssembly component work.
Reach for wasm-toolchain when:
| Trigger | Why |
|---|
User explicitly names wkg or wasm-tools | Honour the explicit request |
Push with custom org.opencontainers.image.* annotations | component registry push does not yet expose annotations |
| Author/publish a raw WIT package (not a built component) | Only wkg wit build + wkg publish do this |
| Resolve WIT dependencies during a language build | wkg wit fetch writes wkg.lock (cross-language) |
Validate / inspect a .wasm file | wasm-tools validate, wasm-tools component wit |
| Convert core module ↔ component | wasm-tools component embed / new / extract |
| Discover pre-built components offline | Curated catalog — see scripts/components.md |
For the lifecycle (init / install / run / compose / search-via-meta-registry)
hand off to the component skill.
Cookbooks
This skill's substantive content lives in cookbooks. Read the relevant
cookbook for the task at hand:
scripts/wkg.md — OCI push/pull with full annotation
control, GHCR / Docker Hub authentication, WIT-package authoring (wkg wit build, wkg publish), wkg.lock semantics, troubleshooting.scripts/wasm-tools.md — validate,
component wit/new/embed/extract, print, dump, metadata add/show,
core-module ↔ component pipelines.scripts/discovery.md — discovery-by-task
workflow: WebFetch awesome-wasm-components → curated catalog fallback →
component registry search (when a meta-registry is available).scripts/components.md — curated catalog of
~25 useful pre-built components and WIT interfaces (markdown table,
3 columns: OCI ref / Language / Description). Slated for deprecation when
meta-registries are reliable.
Binary resolution
This skill prefers pinned binaries shipped under scripts/:
SKILL_DIR=".agents/skills/wasm-toolchain"
WKG="$SKILL_DIR/scripts/wkg"
WASM_TOOLS="$SKILL_DIR/scripts/wasm-tools"
[ -x "$WKG" ] || WKG="wkg"
[ -x "$WASM_TOOLS" ] || WASM_TOOLS="wasm-tools"
Install/refresh via the Justfile:
just install-wkg .agents/skills/wasm-toolchain/scripts
just install-wasm-tools .agents/skills/wasm-toolchain/scripts
If absent, the skill falls back to system-installed wkg / wasm-tools.
Workflow
When this skill is invoked:
- Read the relevant cookbook(s) first — don't dump the cookbook content
into the response; reference it.
- Confirm the binaries are available (skill-local first, system fallback).
- Execute the task. For multi-step pipelines (e.g., pull → validate →
inspect), chain the commands.
- Hand off when appropriate — for component lifecycle ops (run, install,
compose), suggest the
component skill.
Related skills
- component — Default for component lifecycle. Use first unless the
task requires
wkg/wasm-tools-specific functionality (annotations, raw
WIT packages, low-level inspection).
- wasmtime — wasmtime-specific runtime features (
--invoke WAVE,
compile, wizer, objdump, explore, settings, WASIp3 flags).
- wasm-build — Per-language compilation flows (Rust, Python, JS, Go).
Use when the user is building a component from source. Cross-references
wasm-toolchain/scripts/wkg.md for WIT dependency fetch.
References
