From 934a3ffcba35e074672732d38d46af0b2e3c92af Mon Sep 17 00:00:00 2001
From: John Hagler <john.hagler@outlook.com>
Date: Fri, 20 Mar 2026 13:38:23 -0400
Subject: [PATCH] Auto-reply: address bot review edge cases

---
 src/auto-reply/reply/agent-runner-memory.ts   |  7 +++---
 .../reply/agent-runner-utils.test.ts          | 22 ++++++++++++++++++-
 src/auto-reply/reply/agent-runner-utils.ts    |  8 +++++++
 3 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/src/auto-reply/reply/agent-runner-memory.ts b/src/auto-reply/reply/agent-runner-memory.ts
index 47200b64340..819143e6262 100644
--- a/src/auto-reply/reply/agent-runner-memory.ts
+++ b/src/auto-reply/reply/agent-runner-memory.ts
@@ -282,13 +282,14 @@ export async function runMemoryFlushIfNeeded(params: {
     return sandboxCfg.workspaceAccess === "rw";
   })();
 
-  const isCli = isCliProvider(params.followupRun.run.provider, params.cfg);
+  const compactionFallbackOptions = resolveCompactionModelFallbackOptions(params.followupRun.run);
+  const isCli = isCliProvider(compactionFallbackOptions.provider, params.cfg);
   const canAttemptFlush = memoryFlushWritable && !params.isHeartbeat && !isCli;
   let entry =
     params.sessionEntry ??
     (params.sessionKey ? params.sessionStore?.[params.sessionKey] : undefined);
   const contextWindowTokens = resolveMemoryFlushContextWindowTokens({
-    modelId: params.followupRun.run.model ?? params.defaultModel,
+    modelId: compactionFallbackOptions.model ?? params.defaultModel,
     agentCfgContextTokens: params.agentCfgContextTokens,
   });
 
@@ -478,7 +479,7 @@ export async function runMemoryFlushIfNeeded(params: {
     .join("\n\n");
   try {
     await runWithModelFallback({
-      ...resolveCompactionModelFallbackOptions(params.followupRun.run),
+      ...compactionFallbackOptions,
       runId: flushRunId,
       run: async (provider, model, runOptions) => {
         const { embeddedContext, senderContext, runBaseParams } = buildEmbeddedRunExecutionParams({
diff --git a/src/auto-reply/reply/agent-runner-utils.test.ts b/src/auto-reply/reply/agent-runner-utils.test.ts
index 60b1f8ec218..6cb343cd19a 100644
--- a/src/auto-reply/reply/agent-runner-utils.test.ts
+++ b/src/auto-reply/reply/agent-runner-utils.test.ts
@@ -98,10 +98,30 @@ describe("agent-runner-utils", () => {
       provider: "openrouter",
       model: "anthropic/claude-sonnet-4-5",
       agentDir: run.agentDir,
-      fallbacksOverride: ["fallback-model"],
+      fallbacksOverride: ["openrouter/fallback-model"],
     });
   });
 
+  it("rebases model-only fallbacks onto the compaction provider", () => {
+    const run = makeRun({
+      sessionKey: "agent:agent-1:main",
+      config: {
+        agents: {
+          list: [{ id: "agent-1", model: { fallbacks: ["fallback-model", "anthropic/haiku"] } }],
+          defaults: {
+            compaction: {
+              model: "openrouter/anthropic/claude-sonnet-4-5",
+            },
+          },
+        },
+      },
+    });
+
+    const resolved = resolveCompactionModelFallbackOptions(run);
+
+    expect(resolved.fallbacksOverride).toEqual(["openrouter/fallback-model", "anthropic/haiku"]);
+  });
+
   it("keeps the primary provider when compaction model override omits a provider", () => {
     const run = makeRun({
       sessionKey: "agent:agent-1:main",
diff --git a/src/auto-reply/reply/agent-runner-utils.ts b/src/auto-reply/reply/agent-runner-utils.ts
index 4641ea5409a..612679a7b7a 100644
--- a/src/auto-reply/reply/agent-runner-utils.ts
+++ b/src/auto-reply/reply/agent-runner-utils.ts
@@ -180,10 +180,18 @@ export function resolveCompactionModelFallbackOptions(run: FollowupRun["run"]) {
     const provider = override.slice(0, slashIdx).trim();
     const model = override.slice(slashIdx + 1).trim();
     if (provider && model) {
+      const fallbacksOverride = resolved.fallbacksOverride?.map((fallback) => {
+        const trimmed = fallback.trim();
+        if (!trimmed || trimmed.includes("/")) {
+          return trimmed;
+        }
+        return `${provider}/${trimmed}`;
+      });
       return {
         ...resolved,
         provider,
         model,
+        fallbacksOverride,
       };
     }
   }