fix: export only the plugin factory from the plugin entry point

[vtemian]

Found while researching an e2e harness: micode currently logs a plugin load error on every opencode start, and only registers its hooks by luck.

What opencode actually does

It calls every exported function in a plugin module as a plugin factory, and installs each return value as hooks:

function rk($) { let Q=[]; for (let Y of Object.values($)) { Q.push(ok(Y)) } return Q }
async function tk($,Z,Q) { for (let J of rk($.mod)) Q.push(await J(Z, $.options)) }

src/index.ts exported four helpers alongside the plugin. Invoked as (input, options), mergePluginAgents receives options === undefined and throws:

level=ERROR message="failed to load plugin" path=file:///.../dist/index.js
  error="Object.entries requires that input parameter not be null or undefined"

opencode swallows that error and still exits 0, so nothing surfaced it.

Why it worked anyway, and why that is not reassuring

ESM namespace keys are sorted alphabetically, not by declaration order. OpenCodeConfigPlugin starts with a capital O (charCode 79), which sorts ahead of lowercase b (98), so the real plugin registered its hooks before the throw.

Rename that export to something lowercase, or add any export sorting in A–N, and every micode hook disappears silently with a clean exit code.

Verified against the shipped bundle before the fix:

OpenCodeConfigPlugin    OK
buildMcpServers         OK
mergeMcpServers         OK
mergePluginAgentConfig  OK
mergePluginAgents       THREW: Object.entries requires that input parameter not be null or undefined

Note the non-throwing helpers were not harmless either. buildMcpServers(ctx, undefined) returns a map of MCP servers, which opencode would then install as a hooks object.

Fix

Move the four helpers to src/plugin-config.ts. The entry point now exports the plugin alone:

$ bun -e "import('./dist/index.js').then(m => console.log(Object.keys(m)))"
[ "OpenCodeConfigPlugin" ]

Tests import them from their new home; no behaviour changed.

Verification

489 tests pass. A new guard asserts the module's callable surface is exactly ["OpenCodeConfigPlugin"], which is the invariant rather than a proxy for it, since a helper that returns rather than throws is equally wrong.

Mutation-checked: re-exporting a single helper from src/index.ts fails the guard.

The guard deliberately does not invoke the factories. Doing so loads the PTY library and probes for btca, which leaks output into the reporter and takes 20x longer.

[cursor]

Bugbot is not enabled for your account, so this pull request was not reviewed.

Enable Bugbot in the Cursor dashboard to get automatic reviews on future PRs.

[cubic-dev-ai]

No issues found across 4 files

_{Re-trigger cubic}