mda-compat-opencode

# MDA Compat Demo (OpenCode) This skill exists to verify OpenCode SKILL.md compatibility from an MDA-compiled output. Three things are true if OpenCode discovers and loads this skill: 1. The compiled `SKILL.md` parses under OpenCode's loader. 2. The frontmatter `name` matches the package directory name (spec §06-2.1 and OpenCode's own naming rules). 3. The five documented top-level fields (`name`, `description`, `license`, `compatibility`, `metadata`) plus MDA's `integrity` survive the round-trip from `.mda` source to compiled output to runtime ingest. Source: `compat/opencode/source.mda`. Compile: `mda compile compat/opencode/source.mda --target SKILL.md --out-dir compat/opencode/build --integrity`. What this does NOT prove: - That OpenCode parses MDA-extended frontmatter under `metadata.mda.*` (the OpenCode docs do not document any such behavior, and we do not require it; per docs "unknown frontmatter fields are ignored", so passthrough is safe). - That signatures or integrity digests are verified at load time (no current runtime does that). - That `allowed-tools` is honored — OpenCode's public docs do not list this field. MDA may emit it (agentskills.io v1 envelope), but OpenCode's behavior on it is undocumented.