fix(docs): restrict Compatibility to platform only, fix false Linux-only claims, update CONTRIBUTING

Author: markuslf

CONTRIBUTING.md

@@ -912,7 +912,7 @@ Each plugin README follows a fixed structure. See [check-plugins/example/README.
 1. **Overview**: Describes *what* the plugin does. A leading sentence stating the main purpose. This must include at least the text from the plugin's `DESCRIPTION` variable. Followed by subsections:
 
     * **Data Collection**: How data is gathered (shell command, API, psutil, etc.), filtering options, SQLite usage, non-blocking measurement.
-    * **Compatibility**: Supported platforms, required tools or modules.
+    * **Compatibility**: Supported platforms only (Linux, Windows, Cross-platform). Use "Cross-platform" by default since Python runs everywhere. Only use "Linux" if the plugin uses Linux-specific APIs (`/proc`, `systemd`, `dmesg`, `dnf`/`apt`/`yum`, `journalctl`, etc.). The absence of a `.windows` file does not mean the plugin is Linux-only - it just means we do not compile it for Windows. No version requirements, no tool dependencies, no module requirements - those belong in Important Notes or the Fact Sheet.
     * **Important Notes** (optional): Operational edge cases the admin must know before deploying, for example: "Requires sudo", "Only works with Redis 3.0+", "First run returns OK with 'Waiting for more data.'", "After a reboot, counters reset and the check waits for a new baseline". No implementation details - only things that affect deployment and daily operations.
 
 2. **Fact Sheet**: Key properties as a table (download link, check name, check interval, parameters required, Windows support, 3rd party modules, state file path, etc.). Only list applicable rows.

check-plugins/apache-httpd-status/README.md

@@ -13,11 +13,12 @@ Monitors Apache httpd performance via the mod_status endpoint (server-status?aut
 
 **Compatibility:**
 
-* Works with any Apache httpd version that provides `mod_status`
-* Some metrics (connection stats, load averages, processes) are only available in newer versions of `mod_status`
+* Cross-platform
 
 **Important Notes:**
 
+* Works with any Apache httpd version that provides `mod_status`
+* Some metrics (connection stats, load averages, processes) are only available in newer versions of `mod_status`
 * `mod_status` must be loaded and `ExtendedStatus On` must be set in the Apache configuration for full metrics. Without `ExtendedStatus`, only worker counts and scoreboard data are reported.
 * The check alerts on the percentage of busy workers relative to the total number of worker slots (busy + idle + free)
 * Workers in the "Gracefully finishing" (G) state are counted as idle workers, not busy workers

check-plugins/apache-httpd-version/README.md

@@ -12,10 +12,15 @@ Checks the installed Apache httpd version against the endoflife.date API and ale
 
 **Compatibility:**
 
+* Cross-platform
+
+**Important Notes:**
+
 * Runs on all systems where the Apache binary is named either `httpd` or `apache2`
 * Must run on the Apache httpd server itself to detect the installed version
 
 
+
 ## Fact Sheet
 
 | Fact | Value |

check-plugins/apache-solr-version/README.md

@@ -12,9 +12,14 @@ Checks the installed Apache Solr version against the endoflife.date API and aler
 
 **Compatibility:**
 
+* Cross-platform
+
+**Important Notes:**
+
 * Must run on the Apache Solr server itself to detect the installed version
 
 
+
 ## Fact Sheet
 
 | Fact | Value |

check-plugins/atlassian-statuspage/README.md

@@ -12,9 +12,14 @@ Monitors a public Atlassian Statuspage for incidents and maintenance windows. Re
 
 **Compatibility:**
 
+* Cross-platform
+
+**Important Notes:**
+
 * Works with any public status page powered by Atlassian Statuspage (e.g. GitHub, Cloudflare, Datadog)
 
 
+
 ## Fact Sheet
 
 | Fact | Value |

check-plugins/axenita-stats/README.md

@@ -14,9 +14,14 @@ Monitors the health and performance of an Axenita/Achilles installation by query
 
 **Compatibility:**
 
+* Cross-platform
+
+**Important Notes:**
+
 * Requires network access to the Axenita/Achilles API (default: `http://localhost:10000/achilles/ar`)
 
 
+
 ## Fact Sheet
 
 | Fact | Value |

check-plugins/by-ssh/README.md

@@ -14,11 +14,12 @@ Executes a command on a remote host via SSH and evaluates the result. Returns ST
 
 **Compatibility:**
 
-* Requires SSH access to the remote host
-* Requires the `sshpass` command-line tool if password-based authentication is used
+* Cross-platform
 
 **Important Notes:**
 
+* Requires SSH access to the remote host
+* Requires the `sshpass` command-line tool if password-based authentication is used
 * Password-based authentication (`--password`) is not recommended. If used, `ps` will expose the SSH password on the monitoring host.
 * The `--shell` option enables shell expansion for environment variables and file globs but can be a security hazard. Without it, only simple commands without globs or pipes are supported.
 * Supports multiple `--identity` files and `--ssh-option` parameters for fine-grained SSH configuration

check-plugins/by-winrm/README.md

@@ -16,11 +16,11 @@ This plugin executes PowerShell commands or scripts on remote Windows hosts via
 **Compatibility:**
 
 * Runs on Linux and connects to remote Windows hosts
-* Supports NTLM, Kerberos, CredSSP, Basic, and plaintext transports
-* JEA endpoints are only supported with `pypsrp` (via `--winrm-configuration-name`)
 
 **Important Notes:**
 
+* Supports NTLM, Kerberos, CredSSP, Basic, and plaintext transports
+* JEA endpoints are only supported with `pypsrp` (via `--winrm-configuration-name`)
 * This plugin is ideal for retrieving Windows-specific metrics, running custom PowerShell-based health checks (such as inventory, backup status, or failover cluster queries), and accessing systems like Active Directory, Exchange, SQL Server, or Hyper-V
 * It is especially useful in environments where installing a monitoring agent is not possible or desired
 * For Kerberos transport, configure `/etc/krb5.conf` and obtain a ticket via `kinit` before running the plugin. When Kerberos credentials are present in the cache, `--winrm-username` and `--winrm-password` can be omitted.

check-plugins/cometsystem/README.md

@@ -12,10 +12,11 @@ Reads sensor data from Comet System Web Sensors via their JSON API endpoint. Mon
 
 **Compatibility:**
 
-* Works with any Comet System Web Sensor that exposes a `/values.json` endpoint
+* Cross-platform
 
 **Important Notes:**
 
+* Works with any Comet System Web Sensor that exposes a `/values.json` endpoint
 * The repeating `--severity` parameter can be set in different ways:
 
     * `--severity ok|warn|crit|unknown`: High and low alarm severity for all channels and all alarm modes.

check-plugins/crypto-policy/README.md

@@ -11,9 +11,14 @@ Verifies that the system-wide cryptographic policy (as reported by update-crypto
 
 **Compatibility:**
 
+* Cross-platform
+
+**Important Notes:**
+
 * RHEL/CentOS/Fedora and other distributions that ship `update-crypto-policies`
 
 
+
 ## Fact Sheet
 
 | Fact | Value |