Troubleshooting

Start with Mitos’ built-in health check:

ms --health

It reports the runtime paths Mitos searches, clipboard support, configured languages, and tools it could not find. For one language, run ms --health <language>; for example, ms --health rust.

Language features are missing

Language servers are separate programs and must be installed on your system. Check the configured server and whether its executable is available with:

ms --health <language>

After installing or reconfiguring a server, use :lsp-restart. See Language servers and the generated language support table for the server Mitos expects.

If the workspace shows the restricted-mode indicator, local .mitos/languages.toml settings may be blocked. Review the files and run :workspace-trust if you want Mitos to load them. See Workspace trust for the security model.

Themes or syntax files are missing

The ms binary depends on runtime files for themes, queries, and language configuration. Run ms --health to see the searched locations. When using a custom build or unpacking a release manually, point Mitos at the runtime:

export MITOS_RUNTIME=/path/to/mitos/runtime

The installation and building from source pages describe the normal runtime layout.

Configuration does not load

Open the active user configuration with :config-open, then reload it with :config-reload. Syntax errors are shown when Mitos starts or reloads the file.

Project configuration belongs in .mitos/config.toml or .mitos/languages.toml and is subject to workspace trust. You can also test a specific file independently with ms --config <file>.

A key binding does not work

Check the default keymap and your remappings first. Terminal emulators and multiplexers can intercept combinations before Mitos receives them, so test the same binding in a plain terminal session if possible.

Collect logs

Run Mitos with -v, -vv, or -vvv for progressively more detailed logging. Inside the editor, :log-open opens the current log file. To choose a separate path for a reproducible report, start Mitos with --log <file>.

When reporting a problem, include the output of ms --version, the relevant ms --health check, your operating system and terminal, and the smallest steps that reproduce it.