yoi/.yoi/tickets/00001KVHKWNQA/item.md

title	state	created_at	updated_at	assignee	readiness	risk_flags	queued_by	queued_at
Plugin: add Rust PDK and embedded authoring templates for Component Model Tools	closed	2026-06-20T04:16:14Z	2026-06-20T05:53:20Z	null	implementation_ready	plugin pdk component-model authoring templates sdk no-crates-io	workspace-panel	2026-06-20T04:52:58Z

Background

Yoi can now discover Plugin packages, register Tool surfaces, execute sandboxed WASM/Component Model Tool Plugins, enforce Plugin grants, expose https / fs host APIs, and inspect Plugin state through CLI. The next gap is authoring: independent Plugin developers should not need to write raw WIT/ABI glue or copy ad-hoc examples by hand.

This Ticket adds a first-party Rust PDK for Component Model Tool Plugins and embeds a starter template into Yoi resources. It deliberately does not publish to crates.io yet and does not fetch remote templates. The PDK/API and WIT world are still young, so out-of-tree authors should initially use a git rev or generated local path dependency rather than depending on a public semver crate.

Requirements

• Add a Rust PDK crate inside the Yoi workspace.
  • Suggested package name: yoi-plugin-pdk.
  • Suggested path: crates/plugin-pdk.
  • Target Component Model Tool Plugins, not raw core-Wasm as the primary authoring path.
• PDK must be guest-side only.
  • Do not depend on host runtime crates such as pod, llm-worker, tui, or client.
  • Keep dependencies minimal, e.g. serde, serde_json, and WIT binding support.
  • Do not expose ambient fs/network/env authority.
• Provide ergonomic Tool helpers.
  • Typed JSON input parsing.
  • Typed JSON output serialization.
  • Structured ToolError / error-code helpers.
  • ToolContext containing at least the tool name.
  • Helper equivalent to run_json_tool that returns the ToolOutput JSON expected by the Yoi runtime.
• Provide Component Model binding glue.
  • Re-export or wrap generated WIT bindings enough that an author does not need to hand-write raw pointer/length ABI code.
  • Prefer a minimal Guest impl helper first; add a macro only if it is simpler and testable.
• Include embedded authoring templates under runtime resources.
  • Suggested path: resources/plugin/templates/rust-component-tool/.
  • Template includes Cargo.toml, src/lib.rs, plugin.toml, and a short README.
  • Template should be usable by a future yoi plugin new command without network access.
• Template dependency policy:
  • In checkout/dev mode, template may use a local path dependency to crates/plugin-pdk.
  • For out-of-tree authors, docs/template comments should show a git rev dependency pattern.
  • Do not publish or require crates.io for this Ticket.
  • Do not use curl | sh or remote template fetch.
• Include at least one example or fixture Plugin using the PDK.
  • Echo-style Component Model Tool is enough.
  • It should compile to a component artifact through the documented toolchain or, if full component build automation is not yet available, be covered by a clear fixture/test boundary.
• Update Plugin development docs.
  • Explain that Component Model + PDK is the preferred authoring path.
  • Explain that raw core-Wasm ABI is compatibility/transitional.
  • Explain why crates.io publication and remote templates are intentionally deferred.

Acceptance criteria

• Workspace contains a guest-side yoi-plugin-pdk crate.
• A Rust Component Model Tool Plugin can use the PDK to implement a JSON Tool without raw pointer/length ABI code.
• PDK-produced Tool success output is accepted by the existing Yoi Plugin Tool runtime.
• PDK-produced Tool errors are bounded and represented as ordinary Tool result/error content.
• PDK does not grant or imply authority; host-side Plugin grants still decide https / fs / Tool execution access.
• Embedded rust-component-tool template exists in runtime resources and is suitable for future yoi plugin new expansion.
• No crates.io publication is required or performed.
• No remote template fetch is implemented.
• Tests cover:
  • PDK JSON input/output happy path;
  • PDK error output path;
  • PDK sample/template compiles or fixture is validated;
  • sample Plugin can be executed by Yoi component runtime if feasible in current test infrastructure;
  • PDK has no host-runtime crate dependency.
• Validation: focused PDK/plugin tests, cargo fmt --check, relevant cargo check / cargo test, git diff --check, and nix build .#yoi because workspace/package/resources may change.

Non-goals

• Publishing yoi-plugin-pdk to crates.io.
• Remote template fetch or curl | sh setup.
• yoi plugin new/check/pack CLI implementation.
• Multi-language PDKs.
• Service / Ingress authoring.
• WebSocket / inbound HTTP bridge support.
• Replacing Plugin grants with PDK-side checks.

Related work

• 00001KVG0HR9M — Objective: Plugin platform roadmap.
• 00001KVG0HR96 — Plugin Component Model runtime.
• 00001KVFD3YSV — Plugin read-only CLI inspection.
• 00001KVFDX9AF — Plugin https host API.
• 00001KVFDX9AY — Plugin fs host API.
• docs/development/plugin-development.md — current Plugin development guide.