terminal-mcp 0.3.1

MCP server for interactive terminal sessions (SSH, REPLs, database CLIs)

terminal-mcp

MCP server for interactive terminal sessions — SSH, REPLs, database CLIs, and TUI apps inside Claude Code.

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Why This Exists

If you've hit any of these limitations with Claude Code, terminal-mcp solves them:

• "Claude Code can't handle interactive sessions" — The built-in Bash tool runs each command in a fresh subprocess. No persistence, no back-and-forth.
• "SSH not supported in Claude Code" — You can't SSH into a server and run multiple commands across an active connection.
• "Claude Code Bash tool doesn't support REPLs" — Python, Node, Ruby, and other interpreters need a persistent session for multi-line interaction.
• "How to use psql / mysql / redis-cli with Claude Code" — Database CLIs require a live connection that survives across tool calls.
• "Interactive terminal not working in Claude Code" — TUI apps (htop, vim, ncdu, fzf) need a real PTY with special key support.
• "Claude Code can't send arrow keys or Tab" — The Bash tool has no concept of terminal escape sequences.

terminal-mcp fills this gap by exposing MCP tools that create and manage real PTY sessions. Each session runs as a persistent child process; you send input, special keys, and control characters and read output across multiple tool calls for as long as the session lives.

Features

• Persistent PTY sessions — real terminal sessions that survive across tool calls
• Special key support — arrow keys, Tab, Escape, function keys (F1–F12), Home/End, Page Up/Down
• Control characters — Ctrl-C, Ctrl-D, Ctrl-Z, Ctrl-L, and telnet escape
• Two read modes — stream (waits for output to settle) and snapshot (pyte screen buffer for TUI apps)
• ANSI stripping — optional removal of escape sequences for clean text output
• Idle cleanup — automatic session cleanup after configurable timeout
• Session management — list, label, and manage multiple concurrent sessions
• Dynamic resize — resize terminal dimensions on the fly with SIGWINCH support
• Secret input — send passwords without logging them
• Scrollback history — access terminal scrollback buffer beyond the visible screen
• One-shot execution — run a single command without manual session management
• Output truncation — automatic truncation of large outputs to prevent context overflow
• Env var configuration — configure all settings via TERMINAL_MCP_* environment variables
• PyPI distribution — install directly with pip install terminal-mcp

Quickstart

1. Install

From PyPI:

pip install terminal-mcp

From source:

git clone https://github.com/mkpvishnu/terminal-mcp.git
cd terminal-mcp
pip install -e ".[dev]"

2. Register with Claude Code

Add to ~/.claude.json (or your project's .mcp.json):

If installed via pip:

{
  "mcpServers": {
    "terminal": {
      "command": "terminal-mcp"
    }
  }
}

If installed from source:

{
  "mcpServers": {
    "terminal": {
      "command": "python3",
      "args": ["-m", "terminal_mcp.server"],
      "env": {
        "PYTHONPATH": "/absolute/path/to/terminal-mcp"
      }
    }
  }
}

Replace /absolute/path/to/terminal-mcp with the actual path.

3. Use it

session_create  command="python3"  label="repl"
session_read    session_id="abc123"
session_send    session_id="abc123"  input="print('hello')"
session_read    session_id="abc123"
session_close   session_id="abc123"

Tool Reference

session_create

Spawn a persistent PTY terminal session.

Parameter	Type	Required	Default	Description
command	string	Yes	—	Shell command to run (e.g. bash, python3, ssh user@host)
label	string	No	command name	Human-readable label
rows	integer	No	24	Terminal height
cols	integer	No	80	Terminal width
idle_timeout	integer	No	1800	Seconds before auto-close
enable_snapshot	boolean	No	false	Enable pyte screen buffer for snapshot reads
scrollback_lines	integer	No	1000	Scrollback history lines (requires enable_snapshot)

Returns: session_id, label, pid, created_at

session_send

Send input text, a control character, or a special key to an active session. Only one of input, control_char, key, or password may be provided per call.

Parameter	Type	Required	Default	Description
session_id	string	Yes	—	Session ID from session_create
input	string	No	—	Text to send
press_enter	boolean	No	true	Append carriage return after input
control_char	string	No	—	Control character: c d z l ]
key	string	No	—	Special key (see table below)
password	string	No	—	Password or secret (not logged)

Returns: bytes_sent

Supported special keys

Key	Description	Key	Description
up	Arrow up	f1–f12	Function keys
down	Arrow down	home	Home
left	Arrow left	end	End
right	Arrow right	page-up	Page Up
tab	Tab	page-down	Page Down
shift-tab	Shift+Tab	insert	Insert
escape	Escape	delete	Delete
enter	Enter	backspace	Backspace

Supported control characters

Char	Signal	Description
c	SIGINT	Interrupt (Ctrl-C)
d	EOF	End of file / logout (Ctrl-D)
z	SIGTSTP	Suspend (Ctrl-Z)
l	—	Clear screen (Ctrl-L)
]	—	Telnet escape

session_resize

Resize the terminal window of an active session.

Parameter	Type	Required	Default	Description
session_id	string	Yes	—	Session ID
rows	integer	Yes	—	New terminal height
cols	integer	Yes	—	New terminal width

Returns: rows, cols

session_read

Read output from a session.

Parameter	Type	Required	Default	Description
session_id	string	Yes	—	Session ID
mode	string	No	stream	stream or snapshot
timeout	number	No	2.0	Settle timeout in seconds (stream mode)
strip_ansi	boolean	No	true	Strip ANSI escape sequences
scrollback	integer	No	—	Lines of scrollback history (snapshot mode)

Returns: output, bytes_read, prompt_detected, is_alive, truncated, total_lines (when scrollback used)

session_close

Terminate a session gracefully (EOF → SIGHUP → SIGKILL).

Parameter	Type	Required	Description
session_id	string	Yes	Session ID to close

Returns: exit_status

session_exec

Execute a command in a temporary session and return output. The session is automatically cleaned up.

Parameter	Type	Required	Default	Description
exec	string	Yes	—	Command to execute
command	string	No	bash	Shell to use
timeout	number	No	5.0	Seconds to wait for output
rows	integer	No	24	Terminal height
cols	integer	No	80	Terminal width

Returns: output, bytes_read, session_id

session_list

List all active sessions with their status and idle time.

Returns: sessions (array), count

Usage Examples

SSH session

session_create  command="ssh [e-mail]"  label="prod-ssh"
session_read    session_id="a1b2c3d4"  timeout=5.0
session_send    session_id="a1b2c3d4"  password="mypassword"
session_send    session_id="a1b2c3d4"  input="df -h"
session_read    session_id="a1b2c3d4"
session_close   session_id="a1b2c3d4"

Python REPL

session_create  command="python3"  label="repl"
session_read    session_id="e5f6g7h8"
session_send    session_id="e5f6g7h8"  input="import math"
session_send    session_id="e5f6g7h8"  input="print(math.sqrt(144))"
session_read    session_id="e5f6g7h8"
session_close   session_id="e5f6g7h8"

TUI navigation with special keys

session_create  command="python3 -m openclaw configure"  label="openclaw"
session_read    session_id="x1y2z3w4"  timeout=3.0
session_send    session_id="x1y2z3w4"  key="down"
session_send    session_id="x1y2z3w4"  key="down"
session_send    session_id="x1y2z3w4"  key="enter"
session_read    session_id="x1y2z3w4"
session_send    session_id="x1y2z3w4"  key="tab"
session_read    session_id="x1y2z3w4"
session_close   session_id="x1y2z3w4"

Sending Ctrl-C to interrupt

session_send    session_id="a1b2c3d4"  control_char="c"
session_read    session_id="a1b2c3d4"

One-shot command execution

session_exec  exec="ls -la /tmp"
session_exec  exec="python3 -c 'print(42)'"  command="bash"  timeout=10.0

Architecture

Each session is backed by a real PTY allocated via pexpect.spawn. The design has four main parts:

Background reader thread. A daemon thread continuously reads from the PTY file descriptor in 4096-byte chunks and appends bytes to an in-memory buffer. The thread is lock-protected and dies automatically when the child process exits.

Output settling (stream mode). session_read in stream mode polls the buffer until no new bytes have arrived for timeout seconds (default 2s), then returns everything written since the last read call. A hard ceiling of timeout + 10s prevents infinite blocking.

Snapshot mode. When a session is created with enable_snapshot=true, all PTY output is also fed into a pyte virtual screen buffer. session_read with mode="snapshot" returns the current rendered screen — useful for programs that use cursor movement (vim, htop, ncdu).

Idle cleanup. SessionManager runs a background cleanup loop (every 60s by default) that closes sessions idle longer than their idle_timeout. The default timeout is 30 minutes. Concurrent sessions are capped at 10 by default.

Configuration

All settings can be overridden via environment variables prefixed with TERMINAL_MCP_:

Setting	Env Var	Default	Description
max_sessions	TERMINAL_MCP_MAX_SESSIONS	10	Maximum concurrent sessions
idle_timeout	TERMINAL_MCP_IDLE_TIMEOUT	1800	Seconds before auto-close
default_rows	TERMINAL_MCP_DEFAULT_ROWS	24	Default terminal height
default_cols	TERMINAL_MCP_DEFAULT_COLS	80	Default terminal width
read_settle_timeout	TERMINAL_MCP_READ_SETTLE_TIMEOUT	2.0	Output settle timeout
max_output_bytes	TERMINAL_MCP_MAX_OUTPUT_BYTES	100000	Max bytes per read
cleanup_interval	TERMINAL_MCP_CLEANUP_INTERVAL	60	Seconds between cleanup

Per-session overrides for rows, cols, and idle_timeout can be passed to session_create.

Changelog

v0.3.0

• Output truncation — large outputs are now automatically truncated to max_output_bytes (100KB default)
• Environment variable config — all settings configurable via TERMINAL_MCP_* env vars
• session_resize tool — dynamically resize terminal dimensions (sends SIGWINCH)
• Secret input — password parameter on session_send for credentials (redacted from logs)
• Scrollback buffer — pyte.HistoryScreen with configurable history depth; scrollback param on session_read
• session_exec tool — one-shot command execution with automatic session cleanup
• PyPI publishing — pip install terminal-mcp via trusted publishing workflow

v0.2.0

• Special key support — arrow keys, Tab, Escape, function keys (F1–F12), Home/End, Page Up/Down, and more via the key parameter on session_send
• Mutual exclusivity — input, control_char, and key are now validated as mutually exclusive
• Added GitHub Actions CI (Python 3.10–3.13) and CodeQL security scanning
• Added project metadata, classifiers, and MIT license

v0.1.0

• Initial release
• Persistent PTY sessions via pexpect
• Stream and snapshot read modes
• Control character support (Ctrl-C, Ctrl-D, Ctrl-Z, Ctrl-L)
• Session management with idle cleanup

Running Tests

pip install -e ".[dev]"
pytest tests/ -v

Contributing

Contributions are welcome! Please open an issue first to discuss what you'd like to change.

1. Fork the repository
2. Create a feature branch
3. Add tests for new functionality
4. Ensure all tests pass: pytest tests/ -v
5. Submit a pull request

License

MIT