Start here · 03

Troubleshooting

You see Why Fix
sonnet is not a provider/name model string; the provider is one of: … the model has no provider prefix write it as provider/name, such as anthropic/claude-sonnet-4-6; check --model, RIFFER_MODEL and both settings files (precedence)
turbo is not a reasoning level; riffer accepts: off low medium high xhigh max --reasoning or RIFFER_REASONING holds an unknown level use one of the listed levels (Configuration)
…/settings.json is not valid JSON at line 4 column 3 a settings, auth.json or trust.json file doesn’t parse fix the file at that position; riffer-rig never overwrites a broken file
anthropic has no api_key (ANTHROPIC_API_KEY); set it in the environment or run riffer interactively to paste it … no credential was found, and riffer-rig can’t ask (headless, ACP) or the answer was left empty set the variable, paste the key when an interactive riffer asks for it (Providers), or for Anthropic configure the SDK’s credential chain
anthropic is not installed; install it with gem install anthropic … the provider’s SDK gem is missing, and riffer-rig can’t or may not install it run the printed command, or add the gem to your Gemfile (SDK gems)
… is not installed and Bundler manages the load path; add gem … riffer-rig runs under Bundler, which it can’t install into add the printed line to your Gemfile and bundle install
Extension NAME failed to load: … an extension raised while loading, its requires: doesn’t match, or it is named after a core settings key fix the extension; the others still loaded (Error isolation)
Unknown tool in allowlist: NAME --tools names a tool that doesn’t exist check the spelling against the identifiers
MCP server NAME failed to register: … the server isn’t https://, didn’t answer, or is missing a credential use an https:// URL, check the server is up, or set the credential (Secret headers)
Unknown command: NAME no command has that name: a typo, or its extension didn’t load or is disabled check the spelling, then whether the extension that adds it failed to load or is disabled
No saved session in this directory. (headless exits 2) -c found nothing to continue drop -c, or run from the directory the session was saved in
no stdin data received in 3s, proceeding without it; … headless was given a prompt and a stdin that stayed open redirect stdin from /dev/null (Headless)
your project’s rig.rb doesn’t load in headless or ACP it hasn’t been trusted, and those hosts can’t ask run riffer once in the project and answer yes (trust)
an edit to settings.json has no effect mid-session automatic reloading watches only rig.rb files run /reload (Reloading)
Shift-Enter sends instead of starting a new row the terminal doesn’t support the Kitty keyboard protocol use Ctrl-J or Alt-Enter (Terminal)
colour codes in captured output output is going to a terminal-like destination set NO_COLOR=1, or use riffer -p
costs show ~$0.0000 or are missing the model has no pricing in a catalog file add it to a catalog file