diff --git a/tools/README.md b/tools/README.md
index 798446ae2..d515fcc7d 100644
--- a/tools/README.md
+++ b/tools/README.md
@@ -8,3 +8,72 @@ command line tools:
     * Elasticsearch X-Pack Watcher
     * Logpoint queries
 * *merge_sigma*: Merge Sigma collections into simple Sigma rules.
+
+## Sigmac
+
+### Usage
+
+      usage: sigmac [-h] [--recurse] [--filter FILTER]
+                    [--target {es-dsl,es-qs,graylog,kibana,xpack-watcher,logpoint,splunk,grep,fieldlist}]
+                    [--target-list] [--config CONFIG] [--output OUTPUT]
+                    [--backend-option BACKEND_OPTION] [--defer-abort]
+                    [--ignore-not-implemented] [--verbose] [--debug]
+                    [inputs [inputs ...]]
+
+      Convert Sigma rules into SIEM signatures.
+
+      positional arguments:
+        inputs                Sigma input files
+
+      optional arguments:
+        -h, --help            show this help message and exit
+        --recurse, -r         Recurse into subdirectories (not yet implemented)
+        --filter FILTER, -f FILTER
+                              Define comma-separated filters that must match (AND-
+                              linked) to rule to be processed. Valid filters:
+                              level<=x, level>=x, level=x, status=y, logsource=z. x
+                              is one of: low, medium, high, critical. y is one of:
+                              experimental, testing, stable. z is a word appearing
+                              in an arbitrary log source attribute. Multiple log
+                              source specifications are AND linked.
+        --target {es-dsl,es-qs,graylog,kibana,xpack-watcher,logpoint,splunk,grep,fieldlist}, -t {es-dsl,es-qs,graylog,kibana,xpack-watcher,logpoint,splunk,grep,fieldlist}
+                              Output target format
+        --target-list, -l     List available output target formats
+        --config CONFIG, -c CONFIG
+                              Configuration with field name and index mapping for
+                              target environment (not yet implemented)
+        --output OUTPUT, -o OUTPUT
+                              Output file or filename prefix if multiple files are
+                              generated (not yet implemented)
+        --backend-option BACKEND_OPTION, -O BACKEND_OPTION
+                              Options and switches that are passed to the backend
+        --defer-abort, -d     Don't abort on parse or conversion errors, proceed
+                              with next rule. The exit code from the last error is
+                              returned
+        --ignore-not-implemented, -I
+                              Only return error codes for parse errors and ignore
+                              errors for rules with not implemented features
+        --verbose, -v         Be verbose
+        --debug, -D           Debugging output
+
+      Backend options:
+        es-dsl
+          es        : Host and port of Elasticsearch instance (default: http://localhost:9200)
+          output    : Output format: import = JSON search request, curl = Shell script that do the search queries via curl (default: import)
+        es-qs
+          rulecomment: Prefix generated query with comment containing title (default: False)
+        graylog
+          rulecomment: Prefix generated query with comment containing title (default: False)
+        kibana
+          output    : Output format: import = JSON file manually imported in Kibana, curl = Shell script that imports queries in Kibana via curl (jq is additionally required) (default: import)
+          es        : Host and port of Elasticsearch instance (default: localhost:9200)
+          index     : Kibana index (default: .kibana)
+          prefix    : Title prefix of Sigma queries (default: Sigma: )
+        xpack-watcher
+          output    : Output format: curl = Shell script that imports queries in Watcher index with curl (default: curl)
+          es        : Host and port of Elasticsearch instance (default: localhost:9200)
+          mail      : Mail address for Watcher notification (only logging if not set) (default: None)
+        logpoint
+          rulecomment: Prefix generated query with comment containing title (default: False)
+        splunk
+          rulecomment: Prefix generated query with comment containing title (default: False)