ToolPiper offers a coding agent two separate things. Tools let the agent use ToolPiper: its browser, your Mac's apps and settings, files, speech, video and the rest. Engine runs the agent on ToolPiper's models, so its answers come from a model you choose instead of the agent's own cloud. You can turn on either, both or neither. Each is a switch on ToolPiper's Home screen.
| Tools | Engine | |
|---|---|---|
| What it changes | What the agent can do | Which model thinks |
| Without it | The agent has only its own tools | The agent uses its own cloud model |
| Takes effect | In a new session | On your next message |
| Cost | Free tools work on every tier | Free with local models |
Tools
Turn on Tools in the agent's row on Home. ToolPiper runs the agent's own command for you, so the connection is the same as one you would make in Terminal. Then start a new session, because agents load their tools when a session starts.
If ToolPiper can't find the agent's command on your Mac, the row offers the command to copy instead.
Engine in Claude Code
Turn on Engine in the Claude Code row and pick a model. Your normal claude
now answers from that model, including a session that is already open, on its
next message. /model inside Claude Code lists your ToolPiper models.
Turn it off and Claude Code goes back to your Anthropic account, again on the next
message. If you picked a model with /model in that session, run /model once more
to choose an Anthropic one.
The switch writes a few entries to Claude Code's settings file, and it takes them out again when you turn it off. Your access token stays in ToolPiper's own folder, never in that file. If those settings already name another server, credential or pinned model, ToolPiper tells you and changes nothing.
When ToolPiper isn't running
Quitting ToolPiper takes its entries out of Claude Code's settings, so a new
claude session uses your Anthropic account. A session that was already running
on ToolPiper's engine stays pointed at ToolPiper, so your work never moves to the
cloud without you choosing it: it says it can't connect until you reopen ToolPiper
or start a new session. Reopening ToolPiper turns the engine back on.
Tools need ToolPiper running too. An open session says the server disconnected;
use /mcp and choose Reconnect once ToolPiper is back.
Choosing a model
Coding agents send long instructions and many tools, so they need a language model with a large context window. Models that run on your Mac are free. A cloud model you added to ToolPiper runs on your own account and needs Pro, as it does anywhere else in ToolPiper.
Codex and ChatGPT
Tools work for both, and they share one switch because Codex and ChatGPT's Codex mode read the same settings file.