tact is a terminal interface for Nanocodex.
demo.mp4
Tact does not sandbox agent commands by default. The agent can read and modify files and run processes with the same permissions as the user running Tact. For a containerized, credential- isolated setup, see the example development environment, which keeps real OpenAI credentials outside the development container while mounting the workspace and Tact state read-write.
The release installer supports x86-64 and ARM64 glibc-based Linux, as well as Intel and Apple Silicon Macs:
curl --proto '=https' --tlsv1.2 -LsSf \
https://tact.clab.by/install.sh | shIt verifies the release checksum and installs tact in ~/.local/bin without sudo. Set
TACT_INSTALL_DIR to another absolute directory if you prefer a different location.
You can also install the published crate with Cargo:
cargo install tact --lockedTo build the current source instead:
git clone https://github.com/clabby/tact.git
cd tact
cargo install --path .Official release binaries can update themselves:
tact updateThe updater verifies both the release checksum and signature before replacing a release-installer
binary. If Cargo owns the installation, tact instead prints cargo install tact --locked so
Cargo's records stay accurate. Automatic update notifications are shown only by official release
builds.
By default, tact uses the ChatGPT session stored by Codex in $CODEX_HOME/auth.json or
~/.codex/auth.json. If that file does not exist, it looks for OPENAI_API_KEY.
To sign in with a ChatGPT subscription:
tact auth login
tact auth statustact auth logout removes the shared credential file, which also signs Codex out. If you want to
require API-key authentication, pass the key through the environment:
export OPENAI_API_KEY="your-api-key"
tact --auth api-keyAPI keys are never written to tact's configuration or shown in status output.
For scripts and integrations, tact run submits one prompt and streams Nanocodex events as JSONL:
tact run "inspect the workspace"The configuration file is optional. Tact reads $TACT_HOME/config.toml, or
~/.tact/config.toml when TACT_HOME is unset. Select another file with --config PATH or
TACT_CONFIG.
Use config show to discover every available field and inspect the complete effective
configuration after file, environment, command-line, and default values have been applied:
tact config path
tact config showThe default effective configuration looks like this (paths depend on your environment):
[auth]
mode = "auto" # auto, chatgpt, or api-key
file = "/path/to/.codex/auth.json"
[agent]
workspace = "/path/to/workspace"
thinking = "medium" # low, medium, high, xhigh, or max
reasoning_mode = "standard" # standard or pro
fast_mode = false
max_subagents = 32
instructions = ""
append_instructions = ""
web_search = true
image_generation = true
websocket_url = ""
api_base_url = ""
[mcp_servers]
[skills]
enabled = false
roots = []
[memory]
enabled = false
[subagents]
enabled = true
[theme]
mode = "auto" # auto, light, or dark
[theme.light]
text = "reset"
border = "dark-gray"
muted = "dark-gray"
accent = "blue"
code_text = "#262626"
code_background = "#EEEEEE"
thinking_low = "dark-gray"
thinking_medium = "#007878"
thinking_high = "#9A6700"
thinking_xhigh = "red"
thinking_max = "magenta"
[theme.dark]
text = "reset"
border = "dark-gray"
muted = "dark-gray"
accent = "blue"
code_text = "#D7D7D7"
code_background = "#262626"
thinking_low = "gray"
thinking_medium = "cyan"
thinking_high = "yellow"
thinking_xhigh = "red"
thinking_max = "magenta"The workspace defaults to the directory where tact starts. Relative paths in the configuration are resolved from the configuration file's directory; relative command-line paths are resolved from the current directory. Command-line options take precedence over environment variables, which take precedence over the file.
New sessions append concise built-in guidance for orchestrating related tool calls in code mode.
When subagents are enabled, they also append guidance for delegation and multi-agent pipelines.
Configured append_instructions follow that guidance.
Tact loads global instructions from AGENTS.override.md or AGENTS.md in CODEX_HOME, which
defaults to ~/.codex, followed by project instructions from the Git repository root through the
configured workspace.
The main agent options can also come from the environment. For example, --workspace,
--thinking, and --resume correspond to TACT_WORKSPACE, TACT_THINKING, and TACT_RESUME.
The prompt for tact run can be supplied through TACT_PROMPT. Run tact --help for the complete
command-line reference.
The /subagents panel shows the current concurrency limit. Use - and + there to update it.
Use Reload config in the Actions menu after editing the file. Theme changes apply immediately. Most agent settings apply when a session starts or is restored, while effort and fast mode can also be changed during a session. Workspace changes require restarting tact.
All theme options can be set directly under [theme] to apply to both palettes:
[theme]
mode = "auto" # auto, light, or dark
text = "reset"
border = "dark-gray"
muted = "dark-gray"
accent = "blue"
code_text = "#D7D7D7"
code_background = "#262626"
thinking_low = "gray"
thinking_medium = "cyan"
thinking_high = "yellow"
thinking_xhigh = "red"
thinking_max = "magenta"Put any of the color options under [theme.light] or [theme.dark] to override that palette. Colors
may be Ratatui names, indexed values such as 239, or RGB values such as "#AABBCC". Auto mode
follows the operating-system theme while tact is running.
Advanced deployments can set agent.websocket_url and agent.api_base_url, or use the
--websocket-url and --api-base-url options. Leave them unset to use Nanocodex's defaults for the
selected authentication method.
Subagents are enabled by default. Disable their tools and built-in delegation instructions with:
[subagents]
enabled = falseThis setting applies when a session starts or is restored. Reloading the configuration does not
change the tool surface of an already-running session. agent.max_subagents controls concurrency
when the feature is enabled; setting it does not enable or disable subagents. See the
subagent design for the tool, lifecycle, messaging, and authority contracts.
Tact's bounded cross-session memory is disabled by default. Opt in explicitly:
[memory]
enabled = trueMemory is global to the selected Tact configuration, not scoped to a workspace. Tact stores it in
memory/v1.sqlite3 beside the selected config.toml, and agents access it only through explicit
memory tool calls. The corpus is never inserted into prompts automatically. For later user
messages and in-flight steers, Tact adds a fixed, content-free checkpoint asking the agent to
review the conversation and update memory when it finds a durable conclusion. See the
global memory design for the tool contract, limits, privacy model, and evaluation
criteria.
Config reload applies memory-browser availability immediately. Like other agent tool and prompt settings, the agent-facing memory setting applies when a new session starts or is restored; an already-running agent retains the tool surface and instructions with which it was created.
Enter /review while no agent work is active to open a browser-based human review tool for
workspace changes. Tact shows the full branch from trunk by default; you can narrow the range,
inspect the diff, leave overall or inline feedback, and approve or request changes. Tact converts
your review to Markdown and inserts it into the composer so you can edit it before passing it to the
agent. Inline selections can also open a private question thread with the agent; those conversations
help you understand the code but are not included in the rendered review feedback. The browser can
also generate an agent-authored visual overview of the selected range on demand.
Reloading or closing the browser does not cancel the review. Agent question threads remain available, and an answer already in progress continues in the background. Reopen the live URL shown by Tact, or cancel explicitly from the browser or Tact.
The review tool requires a separate browser bundle. The first /review from each official Tact
version asks for confirmation, then lazily downloads and verifies the matching release artifact.
The bundle is downloaded once per Tact version and stored under ~/.tact/review by default.
Development builds do not download browser assets. Install Bun, then build and link the assets into the development Tact directory:
cd web/review
bun install --frozen-lockfile
just install-devTo work on the interface in a browser with sample review data, run:
just devTACT_REVIEW_ASSETS=/absolute/path/to/web/review/dist remains available as a manual override. The
development server watches browser sources, rebuilds them, and reloads connected pages.
Press Ctrl+F or choose Fork session from the Actions menu to open an independent session next
to the current one. The fork starts from the stable conversation history available at that point;
new prompts, model responses, and transcripts then remain independent in each pane.
Tact supports one open fork at a time. Close the fork before creating another. Forked sessions are persisted separately and can be resumed like other sessions.
Tact checkpoints each completed turn and keeps an append-only transcript. Open Resume session from the Actions menu to search sessions for the current workspace, or resume a known ID directly:
tact --resume SESSION_IDTact prints the active session's resume command when it exits. Session files live beside the
selected configuration in private, versioned checkpoints and transcripts directories.
Checkpoints contain the complete model-visible conversation and are not redacted, so treat them as
private data.
Skills are local SKILL.md files containing instructions the model can choose to follow. They are
disabled by default to avoid adding their catalogs to every session's persistent context. Skills
can also direct tool and shell execution, so enable only directories you trust:
[skills]
enabled = true
roots = ["skills", "/path/to/shared-skills"]Type $ at a token boundary in the composer to search the active session's skills. Enter or Tab
inserts the selected $skill-name into the prompt.
When enabled, tact also searches $CODEX_HOME/skills (or ~/.codex/skills) and
~/.agents/skills. A new session discovers the current set of skills. Restored sessions keep the
skill catalog they started with so their instructions remain stable.
Tact supports local stdio servers and remote Streamable HTTP servers. Add a local server with:
tact mcp add filesystem -- \
npx -y @modelcontextprotocol/server-filesystem /path/to/workspaceUse --cwd PATH to set its working directory. To pass a secret from tact's environment, put
--env NAME before --; tact copies the value into that server's configuration without placing it
in shell history or process arguments:
tact mcp add --env API_TOKEN private-server -- command --flagThe resulting TOML contains the copied value. tact config show redacts it, but you should still
protect the configuration file as you would any credential file.
Remote servers refer to environment-variable names instead of storing their values:
tact mcp add docs --url https://example.com/mcp \
--bearer-token-env-var DOCS_MCP_TOKEN \
--header-env X-Tenant-ID=DOCS_TENANT_IDRemote URLs must use HTTP or HTTPS and cannot contain embedded credentials. Each server starts independently, so a broken server does not prevent the session or other servers from working.