# Specification: Cluster Diagnosis and Script Enhancement (`diagnose_and_enhance`)

## Overview
Investigate the root cause of the "critical" status on node `odroid8` and enhance the `cluster_status` script to provide deeper diagnostic information, including Consul health check details, Nomad logs, and LiteFS status via `nomad alloc exec`.

## Functional Requirements
- **Consul Diagnostics:**
    - Update `consul_client.py` to fetch the `Output` field from Consul health checks.
    - Display the specific error message from Consul when a node is in a non-passing state.
- **Nomad Integration:**
    - Implement a `nomad_client.py` (or similar) to interact with the Nomad CLI.
    - **Log Retrieval:** For nodes with health issues, fetch the last 20 lines of `stderr` from the relevant Nomad allocation.
    - **Internal Status:** Implement a method to run `litefs status` inside the container using `nomad alloc exec` to retrieve uptime and replication lag when the HTTP API is unavailable.
- **LiteFS API Investigation:**
    - Investigate why the `/status` endpoint returns a 404 and attempt to resolve it via configuration or by identifying the correct endpoint for LiteFS 0.5.
- **Output Formatting:**
    - Update the CLI table to display the retrieved uptime and replication lag.
    - Add a "Diagnostics" section at the bottom of the output when errors are detected, showing the Consul check output and Nomad logs.

## Non-Functional Requirements
- **CLI Dependency:** The script assumes the `nomad` CLI is installed and configured in the local system's PATH.
- **Language:** Python 3.x.

## Acceptance Criteria
- [ ] Script displays the specific reason for `odroid8`'s critical status from Consul.
- [ ] Script successfully retrieves and displays Nomad stderr logs for failing nodes.
- [ ] Script displays LiteFS uptime and replication lag (retrieved via `alloc exec` or HTTP).
- [ ] The root cause of `odroid8`'s failure is identified and reported.

## Out of Scope
- Automatic fixing of the identified issues (diagnosis only).
- Direct SSH into nodes (using Nomad/Consul APIs/CLIs only).