openclaw - 💡(How to fix) Fix Cron isolated sessions: LiveSessionModelSwitchError when payload.model differs from agent default [2 comments, 3 participants]

Bug Description

Isolated cron jobs with payload.model set to a non-default model (e.g., bailian/qwen3.5-plus when agent default is anthropic/claude-opus-4-6) fail immediately with LiveSessionModelSwitchError on every run.

Version

OpenClaw 2026.3.28 (f9b1079)

Steps to Reproduce

1. Configure an agent with primary model anthropic/claude-opus-4-6
2. Create an isolated cron job with payload.model: "bailian/qwen3.5-plus"
3. Wait for the job to fire (or trigger manually with cron run)
4. Job fails with: LiveSessionModelSwitchError: Live session model switch requested: anthropic/claude-opus-4-6

Root Cause Analysis

The embedded agent runner's run loop calls resolvePersistedLiveSelection() on each iteration. This function calls resolveLiveSessionModelSelection(), which:

1. Resolves defaultModelRef via resolveDefaultModelForAgent({cfg, agentId}) - returns the agent's primary model (Opus)
2. Reads entry.providerOverride and entry.modelOverride from the session store
3. Falls back to defaultModelRef when override fields are empty

The cron runner writes the payload model to entry.model / entry.modelProvider (runtime display fields), but never populates entry.providerOverride / entry.modelOverride. The live switch detection reads the override fields, finds them empty, resolves to the agent default (Opus), and sees a mismatch with the actual running model (Qwen). It throws LiveSessionModelSwitchError.

hasDifferentLiveSessionModelSelection() correctly returns false when the persisted selection is null (no session entry exists). But for cron sessions, entries DO exist (created by pre-run persistence) - they just have the model in the wrong fields.

Expected Behavior

payload.model on isolated cron jobs should work as documented. The cron runner should either:

1. Write providerOverride/modelOverride (not just model/modelProvider) when persisting the pre-run session entry, OR
2. The live switch detection should skip cron sessions, OR
3. resolveLiveSessionModelSelection() should fall back to the caller's values instead of resolveDefaultModelForAgent() when the session has no override fields

Impact

Affects ALL isolated cron jobs where payload.model differs from the agent's primary model. In our deployment, 25 of 29 enabled cron jobs were broken after upgrading to 2026.3.28.

Workaround

Patch the session store to copy model/modelProvider into providerOverride/modelOverride for all cron session entries:

import json
store = json.load(open('path/to/sessions.json'))
for key, entry in store.items():
    if 'cron' not in key:
        continue
    m = entry.get('model', '').strip()
    mp = entry.get('modelProvider', '').strip()
    if m and not (entry.get('modelOverride') or '').strip():
        entry['modelOverride'] = m
        if mp:
            entry['providerOverride'] = mp
with open('path/to/sessions.json', 'w') as f:
    json.dump(store, f, indent=2)

Must be re-run after creating new cron jobs with non-default models.