Log Reader

MCP server for Claude Code — lets Claude start, monitor, search, and detect errors in logs from any project, even ones that don't write log files.

Requirements: Python 3.8+, Claude Code

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Install (one-line, any machine)

SSH (if you have GitHub SSH keys set up):

git clone [email protected]:ankit-jhajhria/log-reader-mcp.git ~/.claude/mcp-servers/log-reader && bash ~/.claude/mcp-servers/log-reader/setup.sh

HTTPS (works without SSH keys):

git clone https://github.com/ankit-jhajhria/log-reader-mcp.git ~/.claude/mcp-servers/log-reader && bash ~/.claude/mcp-servers/log-reader/setup.sh

Restart Claude Code after install.

Ubuntu/Debian users: If setup fails with a venv error, run sudo apt install python3-venv first — the script will tell you this too.

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How to use in a new session

Project with no log files — Option A: tmux (you see it running)

Start your terminal inside tmux once:

tmux new -s myserver

Then tell Claude:

run "docker compose up --build" in my tmux session "myserver"

Claude sends the command to your terminal — you watch it run. To stop:

stop docker in tmux session "myserver"

Claude sends Ctrl+C to the pane. You see it stop in real time.

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Project with no log files — Option B: background (hidden, no terminal needed)

Open Claude Code in your project and say:

run "node server.js" and capture the logs

Claude starts the server in the background, captures all terminal output, and tails the log immediately. Always set the working directory so the command runs from the right folder:

run "npm start" in /home/user/my-node-project and capture the logs

To check for problems:

detect errors in the captured log

To restart after a code change:

restart the server

To stop it:

stop the server

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Project that already writes log files (Django, Rails, etc.)

tail logs/debug.log

detect errors in logs/debug.log

search logs/debug.log for "Traceback" with 3 lines of context

show me new lines in logs/debug.log since line 400

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Don't know where the logs are

list log files in the logs folder

Files modified in the last 60 seconds are marked [active] so you can spot the right one instantly.

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All tools

tmux — direct terminal control (no log files needed)

Tool	What it does
tmux_sessions()	List all running tmux sessions and panes
tmux_new_session(session, command, cwd)	Create a new tmux session, optionally run a command in it
tmux_run(session, command, pane, wait)	Send a command to a tmux pane — runs visibly in your terminal
tmux_read(session, pane, lines)	Read output directly from a tmux pane — no log file needed
tmux_send_keys(session, keys)	Send raw keys like Ctrl+C, Ctrl+D, Enter to stop/control processes

Process management (background — no visible terminal)

Tool	What it does
run_and_capture(command, cwd, log_file)	Start any server in background, capture all output to a file
list_captured_processes()	Show all running/stopped captured processes
stop_process(pid)	Stop a process
restart_process(pid)	Stop and restart with the same command and working directory

Log reading

Tool	What it does
detect_errors(path, last_lines)	Auto-scan for ERROR, Exception, Traceback, WARNING, CRITICAL, fatal
tail_file(path, lines=80)	Last N lines of any log file
get_new_lines(path, after_line)	New lines since line N — use to poll a running server
search_log(path, pattern, context_lines)	Regex/string search with optional surrounding context lines
list_log_files(directory, pattern)	List log files with sizes and active status
file_info(path)	Size, modified time, line count

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Troubleshooting

python3-venv error on Ubuntu/Debian:

sudo apt install python3-venv

Permission denied reading a log file: Some system logs (e.g. /var/log/syslog) require elevated permissions. Run Claude Code with sudo or copy the log to a readable location.

Process exits immediately after run_and_capture: The tool detects this and shows you the output. Common causes: wrong command, port already in use, missing dependencies. Fix the command and try again.