Description

[Description]
nemoclaw config set does not validate whether the --key path corresponds to a recognized OpenClaw config key. Any arbitrary dotpath is accepted and
written to openclaw.json, which can produce an invalid config that OpenClaw rejects at startup with Unrecognized key errors, preventing the agent from
launching.

[Environment]
Device: Ubuntu 22.04 (Linux 5.15.0-171-generic)
Node.js: v22.22.2
npm: 10.9.7
Docker: Docker Engine 29.4.0
OpenShell CLI: openshell 0.0.26
NemoClaw: v0.0.18
OpenClaw: 2026.4.2 (d74a122)

[Steps to Reproduce]

1. Set an invalid key path:
   nemoclaw my-assistant config set --key inference.endpoint --value 'https://api.openai.com/v1'
   Output:
   Reading openclaw config...
   Agent: openclaw
   Key: inference.endpoint
   Old value: "https://api.openai.com/v1"
   New value: "https://api.openai.com/v1"
   Writing config to sandbox (/sandbox/.openclaw/openclaw.json)...
   openclaw config updated.

Note: Some config changes require a sandbox restart to take effect.
Re-run with --restart or recreate with: nemoclaw onboard --recreate-sandbox

2. Verify the config now contains the invalid key:
   nemoclaw my-assistant config get
   Output shows a root-level inference key that OpenClaw does not recognize:
   {
   ...
   "inference": {
   "endpoint": "https://api.openai.com/v1"
   }
   }

3. Launch OpenClaw:
   sandbox@my-assistant:~$ openclaw tui
   Config invalid
   File: ~/.openclaw/openclaw.json
   Problem:

• : Unrecognized key: "inference"

Run: openclaw doctor --fix

[Expected Result]
config set should reject unrecognized key paths before writing, e.g.: Key validation failed: "inference.endpoint" is not a recognized OpenClaw config path.

[Actual Result]
The invalid key is silently written to openclaw.json, corrupting the config and preventing OpenClaw from starting.

[NVB# 6090000]