o

o is a workspace for Ollama's agent harness: the agent core, the tools, and the agent TUI, in one place you can change and test without touching the ollama repo.

What is here

Most of the code is adapted from the ollama repo, with imports rewritten to github.com/ParthSareen/o.

Path	Contains
agent/	The harness core: session, events, tool registry, approvals, compactor, skills
agent/tools/	bash, file, web, and skill tools
cmd/o/	The entry point of the agent TUI (package main)
cmd/tui/chat/	The interactive chat UI (bubbletea)
cmd/launch/	A trimmed shim: the spinner and the types that the TUI uses. The integration runners (claude, codex, …) are not included.
cmd/config/, cmd/internal/	Small support packages for the TUI
sessionstore/	SQLite-backed session persistence. Only in o.
app/	Native macOS app (SwiftUI). Bundles the agent core and talks to it over o --pipe. See app/README.md.
.agents/skills/	Project skills. update-o runs the full build/test/package/install/ship loop for the app + CLI.
api/, auth/, envconfig/, format/, progress/, version/, logutil/	Public support packages
internal/	Internal support packages. These must be copies; you cannot import them across modules.
types/model/	Model capabilities and names

Run

You need a local Ollama server. Start it with ollama serve.

Install:

go install ./cmd/o

Use:

o [model]                # start the interactive TUI (uses the last model)
o [model] "prompt"       # print the answer and exit
o --headless <model>     # headless, prompt from args or stdin
o --resume               # resume the most recent session
o --resume-id <id>       # resume a session by ID
o --list                 # list saved sessions
o --name <text> [model]  # start a new session with a name

Flags: --system, --allow-all-tools (no approval prompts), --no-tools, --multimodal, --context-window, --headless, --pipe, --resume, --resume-id, --list, --name. Run o --help for the full usage text, which includes rules for headless use by agents.

--pipe speaks a machine-readable NDJSON protocol over stdio (prompt/cancel commands in, the full agent event stream out) for UI frontends like app/. It implies --allow-all-tools and --rlm unless you set them explicitly.

The TUI

Slash commands: /sessions selects a session to resume, /name [set <text>] shows or sets the session name, /help lists all commands.

Keys:

Key	Action
ctrl+t	Open nvim in the working directory. O_NVIM overrides the command.
ctrl+g	Open the nvim diff viewer (nvim -c DiffviewOpen). O_NVIM_DIFF overrides the command.

Both keys suspend the TUI and come back when you exit nvim. They need nvim in PATH. /nvim and /diffview do the same but are hidden: they are not in /help or in the completions.

The chat renders markdown: headings, code fences, tables, emphasis, links, images (alt text only), lists, blockquotes, and horizontal rules.

Sessions

o saves sessions to ~/.o/sessions.db (SQLite). Each session gets a UUID, and o appends the messages after each run.

A session can have a name. Set it with --name at launch or with /name set <text> in the TUI. o --list prints the ID, Name, Model, and Title of each session; sessions without a name show (unnamed). o upgrades an old database when it opens it; no manual step is necessary.

Debug server

If no server answers on the default port, o can start a debug server on port 11433 through watchy (OLLAMA_DEBUG=1, loopback only). These rules apply:

• o starts the debug server only if watchy and the ollama binary are installed.
• o never stops or replaces a server that runs.
• o reuses a debug server from an earlier launch.
• If you set OLLAMA_HOST, o uses it as it is.
• If the default server runs, o does nothing.

To manage the debug server:

watchy logs o-ollama-debug-11433
watchy stop o-ollama-debug-11433

Differences from upstream

o adds these on top of the ollama code:

• sessionstore/ — session persistence, only in o.
• cmd/o/main.go — new runner. It does the same as launchInteractiveModel without the cmd package plumbing.
• cmd/o/headless.go — headless mode, only in o.
• cmd/o/model_helpers.go — simplified copies of showOrPullModel, ensureCloudStub, and inferThinkingOption. The :cloud suggestion flow is removed.
• cmd/launch/agent_shim.go — hand-maintained types that the TUI uses, instead of the full cmd/launch package.
• cmd/tui/chat/ — session names (--name, /name), the nvim keys (ctrl+t, ctrl+g), and the extended markdown renderer.
• patches/17295-syntax-highlighting.diff — the changes from ollama/ollama#17295 (syntax highlighting in fenced code blocks), applied in-tree. When the PR merges upstream, delete the patch.

License: MIT (same as ollama).