README.md•8.48 kB
Prometheus MCP Server
=====================
[](https://crates.io/crates/prometheus-mcp)
[](https://docs.rs/prometheus-mcp)
[](https://github.com/brenoepics/prometheus-mcp/actions/workflows/release.yml)
[](https://github.com/brenoepics/prometheus-mcp/releases)
[](https://hub.docker.com/r/brenoepics/prometheus-mcp)
[](LICENSE)
A minimal Model Context Protocol (MCP) server focused on reading from Prometheus. It exposes Prometheus discovery and query tools to MCP-compatible apps and includes a convenient CLI for local queries.
Highlights
- Instant and range queries via Prometheus HTTP API
- Discovery helpers: list metrics, get metadata, series selectors, label values
- Optional internal metrics exporter at /metrics (disabled by default)
- Works as a stdio MCP server or a one-off CLI
Container images
----------------
Images are published to both Docker Hub and GHCR:
- Docker Hub: `brenoepics/prometheus-mcp`
- GHCR: `ghcr.io/brenoepics/prometheus-mcp`
Quickstart
----------
Pick your preferred install method.
- From crates.io (installs the `prometheus-mcp` binary):
```bash
cargo install prometheus-mcp
prometheus-mcp --help
```
- Prebuilt binaries (GitHub Releases):
- Download the latest release for your OS/arch:
https://github.com/brenoepics/prometheus-mcp/releases
- Docker (pull from Docker Hub or GHCR):
```bash
# Docker Hub
docker pull brenoepics/prometheus-mcp:latest
# or GHCR
docker pull ghcr.io/brenoepics/prometheus-mcp:latest
# Run the MCP server against a local Prometheus (pick one image)
docker run --rm -it brenoepics/prometheus-mcp:latest --mcp \
--prometheus-url http://host.docker.internal:9090
```
Installation
-----------
Build from source (Rust):
```bash
cargo build --release
# binary at ./target/release/prometheus-mcp
```
Or build a Docker image locally:
```bash
docker build -t prometheus-mcp:latest .
```
Usage (CLI)
-----------
The CLI mirrors the tools exposed over MCP.
- Instant query
```bash
prometheus-mcp query --query 'up' --prometheus-url http://localhost:9090
# optionally set an evaluation time
prometheus-mcp query --query 'up' --time '2025-09-27T12:00:00Z'
```
- Range query
```bash
prometheus-mcp range --query 'rate(http_requests_total[5m])' \
--start '2025-09-27T12:00:00Z' --end '2025-09-27T13:00:00Z' --step '30s'
```
- List metric names
```bash
prometheus-mcp list-metrics
```
- Metric metadata
```bash
prometheus-mcp metadata --metric 'up'
```
- Series selectors (repeat --selector)
```bash
prometheus-mcp series --selector 'up' --selector 'node_cpu_seconds_total{mode="idle"}'
```
- Label values
```bash
prometheus-mcp label-values --label 'job'
```
MCP server (stdio)
------------------
Start the MCP server over stdio:
```bash
prometheus-mcp --mcp --prometheus-url http://localhost:9090
```
Optional: enable internal metrics at /metrics (default off):
```bash
prometheus-mcp --mcp --metrics-exporter --metrics-port 9091
```
Running in Docker
-----------------
Use the published image from Docker Hub (or GHCR alternative shown):
```bash
# Start the MCP server (macOS/Windows: host.docker.internal works; Linux see alternatives below)
docker run --rm -it brenoepics/prometheus-mcp:latest --mcp \
--prometheus-url http://host.docker.internal:9090
```
Linux alternatives when Prometheus runs on the host:
```bash
# Use host networking (Linux only)
docker run --rm -it --network host brenoepics/prometheus-mcp:latest --mcp \
--prometheus-url http://localhost:9090
# Without host network: map host gateway and use host.docker.internal
docker run --rm -it --add-host=host.docker.internal:host-gateway \
brenoepics/prometheus-mcp:latest --mcp \
--prometheus-url http://host.docker.internal:9090
```
One-off CLI in the container:
```bash
# Instant query
docker run --rm brenoepics/prometheus-mcp:latest query --query 'up' \
--prometheus-url http://host.docker.internal:9090
# Range query
docker run --rm brenoepics/prometheus-mcp:latest range --query 'rate(http_requests_total[5m])' \
--start '2025-09-27T12:00:00Z' --end '2025-09-27T13:00:00Z' --step '30s' \
--prometheus-url http://host.docker.internal:9090
```
Basic Auth
----------
Pass credentials via environment variables or CLI flags.
- Environment variables:
```bash
export PROMETHEUS_URL=https://prom.example.com
export PROMETHEUS_USERNAME=api
export PROMETHEUS_PASSWORD=secret
prometheus-mcp --mcp
```
- CLI flags:
```bash
prometheus-mcp --mcp \
--prometheus-url https://prom.example.com \
--prometheus-username api \
--prometheus-password secret
```
- Docker with env vars:
```bash
docker run --rm -it \
-e PROMETHEUS_URL=https://prom.example.com \
-e PROMETHEUS_USERNAME=api \
-e PROMETHEUS_PASSWORD=secret \
brenoepics/prometheus-mcp:latest --mcp
```
Configuration
-------------
All settings can be provided via environment variables; some also via flags.
| Name | Type | Default | CLI flag | Description |
|------|------|---------|----------|-------------|
| PROMETHEUS_URL | string (URL) | http://localhost:9090 | --prometheus-url | Base URL of your Prometheus server |
| PROMETHEUS_TIMEOUT | integer (seconds) | 10 | — | HTTP request timeout |
| PROMETHEUS_RETRIES | integer | 3 | — | Number of retries for Prometheus API calls |
| PROMETHEUS_RETRY_BACKOFF_MS | integer (ms) | 500 | — | Time to wait between retries |
| PROMETHEUS_MIN_INTERVAL_MS | integer (ms) | — | — | Minimum interval between query requests (basic rate limit) |
| PROMETHEUS_CACHE_TTL_SECS | integer (seconds) | — | — | TTL for simple in-process caches (list metrics and label values) |
| PROMETHEUS_USERNAME | string | — | --prometheus-username | Basic auth username |
| PROMETHEUS_PASSWORD | string | — | --prometheus-password | Basic auth password |
| — | boolean | false | --mcp | Start MCP server over stdio |
| — | boolean | false | --metrics-exporter | Enable internal Prometheus metrics at /metrics |
| — | integer (port) | 9091 | --metrics-port | Port for /metrics when exporter is enabled |
See docs/configuration.md for notes and examples.
Accessing from Claude Desktop
-----------------------------
Follow the official guide to locate `claude_desktop_config.json`:
https://modelcontextprotocol.io/quickstart/user#for-claude-desktop-users
Minimal Docker-based entry:
```json
{
"mcpServers": {
"prometheus": {
"command": "docker",
"args": ["run", "--rm", "-i", "brenoepics/prometheus-mcp:latest"]
}
}
}
```
With host Prometheus and exporter (macOS/Windows):
```json
{
"mcpServers": {
"prometheus": {
"command": "docker",
"args": [
"run", "--rm", "-i",
"-p", "9091:9091",
"brenoepics/prometheus-mcp:latest",
"--mcp",
"--prometheus-url", "http://host.docker.internal:9090",
"--metrics-exporter",
"--metrics-port", "9091"
]
}
}
}
```
With Basic Auth via environment variables:
```json
{
"mcpServers": {
"prometheus": {
"command": "docker",
"args": [
"run", "--rm", "-i",
"-e", "PROMETHEUS_URL=https://prom.example.com",
"-e", "PROMETHEUS_USERNAME=api",
"-e", "PROMETHEUS_PASSWORD=secret",
"brenoepics/prometheus-mcp:latest", "--mcp"
]
}
}
}
```
More examples: see docs/claude-desktop.md.
Debugging
---------
Use the MCP Inspector to exercise the server interactively:
```bash
npx @modelcontextprotocol/inspector
```
Connect with transport "STDIO", command `prometheus-mcp`, and optional args `--mcp --prometheus-url http://localhost:9090`.
Logs are appended to /tmp/mcp.jsonl; tail it with:
```bash
tail -f /tmp/mcp.jsonl
```
Security Considerations
-----------------------
- The server does not provide authentication itself; when running outside stdio, keep it on localhost.
- Handle credentials via environment variables or your secret manager. Avoid committing secrets.
License
-------
Apache-2.0