feat(opencode/session): default-on hivemind loop primitive (#266 Phase 2)

GRUNTCODE.md

@@ -12,7 +12,7 @@ Current patches (each tracked in [hivemind #222](https://github.com/grunt-it/hiv
 2. **Attach subscribes to all session message updates.** When a wake fires via `/session/<id>/prompt_async`, the attach-client TUI renders the response. (Without this patch, externally-triggered messages land in the server's db but never reach the user's screen.)
 3. **`OPENCODE_SERVER_URL` propagation.** The attach binary reads and propagates this env var to all subprocesses (MCP children, etc.) so agents can find their serve daemon without a launch-script shim.
 4. **`--peer-id <id>` flag.** Lets launch scripts set the tab's hivemind peer-id at startup instead of via TAKEOFF gymnastics. Powers patch #1.
-5. **Turn-end hook into the hivemind loop primitive ([#266](https://github.com/grunt-it/hivemind-mcp/issues/266) Phase 1).** Behind feature flag `OPENCODE_HIVEMIND_LOOP_ENABLED=1`. Every step-finish fires `hivemind_record_turn_end` into the hivemind MCP, which evaluates the three-layer goal-loop contract + decides to auto-wake the same peer (`continue`), wake the parent peer (`escalate` / `await-review`), or no-op. Per-tool-call `hivemind_loop_progress` bumps the progress timestamp. Fire-and-forget via `Effect.forkIn(scope)` — hook failures NEVER break the TUI. Opt-in per-tab via env var in Phase 1; planned default-on in Phase 2 after validating in the wild.
+5. **Turn-end hook into the hivemind loop primitive ([#266](https://github.com/grunt-it/hivemind-mcp/issues/266) Phase 2 — default-on).** Every step-finish fires `hivemind_record_turn_end` into the hivemind MCP, which evaluates the three-layer goal-loop contract + decides to auto-wake the same peer (`continue`), wake the parent peer (`escalate` / `await-review`), or no-op. Per-tool-call `hivemind_loop_progress` bumps the progress timestamp. Fire-and-forget via `Effect.forkIn(scope)` — hook failures NEVER break the TUI. ON by default as of Phase 2; opt out for a specific tab/session via `OPENCODE_HIVEMIND_LOOP_ENABLED=0`. Pairs with a 3-turn grace window in `hivemind-mcp` (#266 Phase 2) — peers have 3 turns to call `hivemind_set_loop_goal` before the MCP escalates with `violationKind=missing-loop-goal`.
 
 Everything else is opencode upstream. We rebase against `anomalyco/opencode:dev` weekly.
 

packages/opencode/src/effect/runtime-flags.ts

@@ -55,14 +55,16 @@ export class Service extends ConfigService.Service<Service>()("@opencode/Runtime
   bashDefaultTimeoutMs: positiveInteger("OPENCODE_EXPERIMENTAL_BASH_DEFAULT_TIMEOUT_MS"),
   experimentalNativeLlm: bool("OPENCODE_EXPERIMENTAL_NATIVE_LLM"),
   /**
-   * Loop primitive (#266 Phase 1) — when true, the session processor fires
+   * Loop primitive (#266 Phase 2 — default-on) — when true, the session processor fires
    * hivemind_record_turn_end after every step-finish + hivemind_loop_progress after every
    * tool-result. The MCP then decides whether to auto-wake the same peer (continue), wake
-   * the parent (escalate), or no-op. Default off in Phase 1; opt-in per-tab via env var;
-   * planned default-on in Phase 2 after validating in the wild. Failure of the hook is
-   * always non-fatal — the TUI is never blocked or thrown into on a hivemind error.
+   * the parent (escalate / await-review), or no-op. Default ON as of Phase 2 — Phase 1
+   * proved the hook is reliably non-fatal (forkIn(scope) + interrupted-error swallow) and
+   * the auto-drive payoff is significant. To opt OUT for a specific tab/session, set
+   * `OPENCODE_HIVEMIND_LOOP_ENABLED=0` in the env. Failure of the hook is always non-fatal —
+   * the TUI is never blocked or thrown into on a hivemind error.
    */
-  hivemindLoopEnabled: bool("OPENCODE_HIVEMIND_LOOP_ENABLED"),
+  hivemindLoopEnabled: Config.boolean("OPENCODE_HIVEMIND_LOOP_ENABLED").pipe(Config.withDefault(true)),
   client: Config.string("OPENCODE_CLIENT").pipe(Config.withDefault("cli")),
 }) {}
 

packages/opencode/src/session/hivemind-loop-hook.ts

@@ -19,9 +19,10 @@ type MCPShape = MCP.Interface
  * pipes through Effect.ignore + Effect.forkIn(scope) so the TUI never blocks on the MCP
  * call and never sees an exception from a slow / failing hivemind connection.
  *
- * Feature-flagged: opt-in via OPENCODE_HIVEMIND_LOOP_ENABLED=1 (RuntimeFlags.hivemindLoopEnabled).
- * Off by default in Phase 1 so users can adopt per-tab + we can flip the global default in
- * Phase 2 after validating in the wild.
+ * Feature-flagged via OPENCODE_HIVEMIND_LOOP_ENABLED (RuntimeFlags.hivemindLoopEnabled).
+ * DEFAULT-ON as of Phase 2 — Phase 1 validation proved the hook is reliably non-fatal +
+ * the auto-drive payoff is significant. To opt out for a specific tab/session, set
+ * OPENCODE_HIVEMIND_LOOP_ENABLED=0 in the env.
  */
 
 const log = Log.create({ service: "session.hivemind-loop-hook" })
@@ -90,7 +91,7 @@ function buildTurnSummary(messageId: MessageV2.Assistant["id"]) {
  * The MCP wraps evaluateLoop + fires the wake/escalation internally. This side just sends
  * the turn-end event and forgets.
  *
- * Off when OPENCODE_HIVEMIND_LOOP_ENABLED is unset/false — silent no-op.
+ * Silent no-op when OPENCODE_HIVEMIND_LOOP_ENABLED=0 (Phase 2 default is ON).
  */
 export const recordTurnEnd = Effect.fn("HivemindLoopHook.recordTurnEnd")(function* (input: {
   enabled: boolean
@@ -136,7 +137,7 @@ export const recordTurnEnd = Effect.fn("HivemindLoopHook.recordTurnEnd")(functio
  * Fire hivemind_loop_progress after a tool-result. Cheap call — just bumps
  * last_loop_progress_at so evaluate_loop sees fresh activity. Same fire-and-forget guarantee.
  *
- * Off when OPENCODE_HIVEMIND_LOOP_ENABLED is unset/false — silent no-op.
+ * Silent no-op when OPENCODE_HIVEMIND_LOOP_ENABLED=0 (Phase 2 default is ON).
  */
 export const loopProgress = Effect.fn("HivemindLoopHook.loopProgress")(function* (input: {
   enabled: boolean

packages/opencode/src/session/processor.ts

@@ -623,10 +623,11 @@ export const layer = Layer.effect(
                 messageID: ctx.assistantMessage.parentID,
               })
               .pipe(Effect.ignore, Effect.forkIn(scope))
-            // Hivemind loop primitive (#266 Phase 1): fire the turn-end event into hivemind-mcp.
-            // The MCP runs evaluateLoop + decides auto-wake / auto-escalate / no-op. Off by
-            // default; opt-in via OPENCODE_HIVEMIND_LOOP_ENABLED. Always fire-and-forget —
-            // hivemind failure must never break the TUI.
+            // Hivemind loop primitive (#266 Phase 2 — default-on): fire the turn-end event into
+            // hivemind-mcp. The MCP runs evaluateLoop + decides auto-wake / auto-escalate /
+            // await-review / no-op. ON by default; opt out per tab via
+            // OPENCODE_HIVEMIND_LOOP_ENABLED=0. Always fire-and-forget — hivemind failure must
+            // never break the TUI.
             yield* HivemindLoopHook.recordTurnEnd({
               enabled: flags.hivemindLoopEnabled,
               mcp: mcpOption,