Loki MCP Server

Loki MCP Server is a Model Context Protocol (MCP) interface for querying Grafana Loki logs using logcli. The server enables AI assistants to access and analyze log data from Loki directly.

Features

Query Loki logs with full LogQL support
Get label values and metadata
Authentication and configuration support via environment variables or config files
Provides formatted results in different output formats (default, raw, JSON lines)

Prerequisites

Node.js v16 or higher
TypeScript
Grafana Loki logcli installed and accessible in your PATH
Access to a Loki server instance

Installation

Clone the repository:

git clone https://github.com/yourusername/loki-mcp.git
cd loki-mcp

Install dependencies:

npm install

Build the project:

npm run build

Configuration

You can configure Loki access using:

Environment Variables

LOKI_ADDR: Loki server address (URL)
LOKI_USERNAME: Username for basic auth
LOKI_PASSWORD: Password for basic auth
LOKI_TENANT_ID: Tenant ID for multi-tenant Loki
LOKI_BEARER_TOKEN: Bearer token for authentication
LOKI_BEARER_TOKEN_FILE: File containing bearer token
LOKI_CA_FILE: Custom CA file for TLS
LOKI_CERT_FILE: Client certificate file for TLS
LOKI_KEY_FILE: Client key file for TLS
LOKI_ORG_ID: Organization ID for multi-org setups
LOKI_TLS_SKIP_VERIFY: Skip TLS verification ("true" or "false")
LOKI_CONFIG_PATH: Custom path to config file
DEBUG: Enable debug logging

Config Files

Alternatively, create a logcli-config.yaml file in one of these locations:

Custom path specified by LOKI_CONFIG_PATH
Current working directory
Your home directory (~/.logcli-config.yaml)

Example config file:

addr: https://loki.example.com
username: user
password: pass
tenant_id: mytenant

Usage

Start the server:

npm start

For development:

npm run dev

Available MCP Tools

query-loki

Query logs from Loki with filtering options.

Parameters:

query (required): Loki query string (LogQL)
from: Start timestamp (e.g. "2023-01-01T12:00:00Z")
to: End timestamp (e.g. "2023-01-01T13:00:00Z")
limit: Maximum number of logs to return
batch: Batch size for query results
output: Output format ("default", "raw", or "jsonl")
quiet: Suppress query metadata
forward: Display results in chronological order

get-label-values

Retrieve all values for a specific label.

Parameters:

label (required): Label name to get values for

get-labels

Retrieve all available labels.

No parameters required.

Development

# Run linter
npm run lint

# Fix linting issues
npm run lint:fix

# Run tests
npm run test

License

This project is licensed under the MIT License - see the LICENSE.md file for details.

yangroro/loki-mcp