Add docs on enabling command auto-completion

README.md

@@ -117,6 +117,34 @@ Additional options that have an accompanying environment variable include:
   before a request is sent to CVE Services. Truthy values for the environment variable are:
   `1`, `t`, `yes`.
 
+### Command Autocompletion
+
+Autocompletion of subcommands is supported for the following shells:
+
+#### Bash
+
+Add the following line to your `~/.bashrc` file:
+
+```bash
+eval "$(_CVE_COMPLETE=bash_source cve)"
+```
+
+#### ZSH
+
+Add the following line to your `~/.zshrc` file:
+
+```bash
+eval "$(_CVE_COMPLETE=zsh_source cve)"
+```
+
+#### Fish
+
+Add the following line to a `~/.config/fish/completions/cve.fish` file:
+
+```bash
+eval (env _CVE_COMPLETE=fish_source cve)
+```
+
 ## CLI Usage Examples
 
 Available options and commands can be displayed by running `cve --help`. The following are
@@ -220,6 +248,13 @@ pip install tox
 pip install -e .[dev]
 ```
 
+To enable command autocompletion when using a virtual environment, add the line noted in `Command Autocompletion`
+above to your `venv/bin/activate` file, for example:
+
+```bash
+echo 'eval "$(_CVE_COMPLETE=bash_source cve)"' >> venv/bin/activate
+```
+
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