LM-5: fixture-level AC1 compaction, AC3, AC4 and AC5 (#380)

apps/desktop/src/main/engine/local-models/execution.ts

@@ -54,6 +54,18 @@ function refuseProjectConfiguration(cwd: string): void {
   }
 }
 
+/**
+ * Codex words every HTTP 500 as a cloud service under load ("We're currently experiencing high demand"). From a
+ * loopback server that is not what happened: it is the person's own server failing, often out of memory. Codex's
+ * text stays in the detail; the turn's error says what is known (#380 AC4).
+ */
+function truthful(result: TurnResult): TurnResult {
+  if (result.status !== "failed") return result;
+  const detail = result.detail as { turnError?: { codexErrorInfo?: unknown } } | undefined;
+  if (detail?.turnError?.codexErrorInfo !== "internalServerError") return result;
+  return { ...result, error: "The local server returned an internal error (HTTP 500). Check its log: it may have run out of memory or crashed while loading the model. Modex didn't retry the turn or switch models." };
+}
+
 export class LocalExecution {
   /** The child owning each thread's native conversation, with the key it was started for. */
   private readonly children = new Map<string, { key: string; backend: CodexBackend; home: string; provenance?: LocalConfigurationProvenance }>();
@@ -146,7 +158,7 @@ export class LocalExecution {
         this.children.set(thread.id, owned);
       }
       // Effort, fast mode and service tiers are cloud-model settings with no local qualification: none is sent.
-      return await owned.backend.runTurn(text, { ...opts, effort: undefined, fast: false }, sink, signal);
+      return truthful(await owned.backend.runTurn(text, { ...opts, effort: undefined, fast: false }, sink, signal));
     } catch (error) {
       return signal.aborted ? { status: "interrupted" } : { status: "failed", error: (error as Error).message };
     } finally { release?.(); }

apps/desktop/src/main/engine/local-models/run-policy.ts

@@ -62,6 +62,8 @@ export interface LocalContextEvidence {
 
 /** Keys a layer other than Modex's session flags may not set: the inference destination, the model, its context and the tools reaching it. */
 const GOVERNED = ["model", "model_provider", "model_providers", "openai_base_url", "oss_provider", "model_catalog_json", "model_context_window", "model_auto_compact_token_limit",
+  // Native compaction: what it sends the provider and when it runs (#380 AC1; key names from codex-cli 0.166.0).
+  "compact_prompt", "model_auto_compact_token_limit_scope", "model_post_turn_compact_threshold_percent", "model_async_compact_threshold_percent",
   "model_reasoning_summary", "model_reasoning_effort", "service_tier", "web_search", "features", "mcp_servers", "shell_environment_policy", "plugins", "hooks", "marketplaces",
   "profile", "profiles", "projects", "notify", "otel", "tools", "developer_instructions", "model_instructions_file", "agents", "cloud"];
 const MANAGED = new Set(["mdm", "system", "enterpriseManaged", "legacyManagedConfigTomlFromFile", "legacyManagedConfigTomlFromMdm"]);
@@ -131,6 +133,8 @@ export function admitLocalConfiguration(read: ConfigRead, requirements: Requirem
   want(`model_providers.${expected.provider}.requires_openai_auth`, provider.requires_openai_auth, false);
   want(`model_providers.${expected.provider}.env_key`, provider.env_key ?? null, expected.tokenEnv);
   want(`model_providers.${expected.provider}.request_max_retries`, provider.request_max_retries, 0);
+  // A dropped stream is otherwise re-sent whole: the turn reports the drop instead (#380 AC4).
+  want(`model_providers.${expected.provider}.stream_max_retries`, provider.stream_max_retries, 0);
   for (const name of ["experimental_bearer_token", "auth", "http_headers", "env_http_headers", "query_params"]) want(`model_providers.${expected.provider}.${name}`, provider[name] ?? null, null);
   want("model_context_window", config.model_context_window, expected.contextTokens);
   want("web_search", config.web_search, "disabled");

apps/desktop/src/main/engine/runner.ts

@@ -1164,8 +1164,9 @@ export class ThreadRunner {
     // External edits remain fenced until the renderer adopts the canonical state.
     if (this.restartHold?.kind !== "owner-removal" || (!opts.fromRouter && !opts.automaticTitle)) this.assertNotRestarting();
     // Resume handles and account bindings are main-owned, even if an IPC caller sends extra keys.
-    // A local target is chosen on this Mac: a paired desktop's patch never carries one.
-    const localKeys = opts.by === "paired-desktop" ? [] : ["localTarget", "localContextTokens"];
+    // A local target is chosen, changed and cleared on this Mac's own window only (#380 AC5): a paired desktop's,
+    // the phone's or an unnamed caller's patch never carries one.
+    const localKeys = opts.by === "desktop" ? ["localTarget", "localContextTokens"] : [];
     patch = Object.fromEntries(Object.entries(patch).filter(([key]) =>
       ["mode", "model", "title", "backend", "plan", "effort", "auto", "approvals", ...localKeys].includes(key))) as ThreadPatch;
     if (patch.approvals !== undefined && !APPROVAL_POLICIES.includes(patch.approvals)) delete patch.approvals;