mcp-rancher

<!-- mcp-name: io.github.rex/rancher-mcp --> <p align="center"> <img src="https://raw.githubusercontent.com/rex/mcp-rancher/main/docs/assets/header.png" alt="MCP Rancher — the capability-aware control plane for AI-assisted Rancher operations" /> </p> <p align="center"> <a href="https://github.com/rex/mcp-rancher/actions/workflows/validate.yml"><img src="https://img.shields.io/github/actions/workflow/status/rex/mcp-rancher/validate.yml?branch=main&label=CI" alt="CI" /></a> <a href="https://modelcontextprotocol.io"><img src="https://img.shields.io/badge/MCP-server-2b6cd0" alt="MCP server" /></a> <a href="docs/tool-manifest.json"><img src="https://img.shields.io/badge/tools-321-2b6cd0" alt="321 tools" /></a> <a href="https://www.python.org/"><img src="https://img.shields.io/badge/python-3.12%2B-3776ab?logo=python&logoColor=white" alt="Python 3.12+" /></a> <a href="https://github.com/microsoft/pyright"><img src="https://img.shields.io/badge/types-pyright%20strict-blue" alt="Pyright strict" /></a> <a href="LICENSE"><img src="https://img.shields.io/badge/license-MIT-lightgrey" alt="MIT license" /></a> </p> <p align="center"> Operate Rancher-managed Kubernetes through any MCP client — discovery, generic resource access, and curated operator workflows, wrapped in an audit-logged, rate-limited, confirmation-guarded safety model. </p> <p align="center"> <a href="#quick-start">Quick start</a> · <a href="#the-tool-surface">Tool surface</a> · <a href="#architecture">Architecture</a> · <a href="#safety-model">Safety model</a> · <a href="#compatibility">Compatibility</a> · <a href="#development">Development</a> </p> --- ## Why this exists Rancher is how real fleets run Kubernetes — and it speaks **two APIs** (the legacy Norman `/v3` plane and the modern Steve `/v1` plane), varies by version, and wraps every cluster behind its own proxy. Pointing a generic Kubernetes MCP server at it misses everything Rancher-specific; pointing an agent at raw `kubectl` gives up auditability, guardrails, and the management-plane view entirely. **MCP Rancher** is built for that reality: - **Capability-aware, not version-naive.** It detects what each connected Rancher actually supports instead of assuming. One binary spans **2.6.5 → 2.9.3** with the same tool surface. - **Multi-instance first.** Lab, staging, prod — configure them all; mark prod `read_only: true` and every mutation is refused at the config layer, before any guard even has to fire. - **Nothing is out of reach.** Curated tools cover the common 95%; the generic engine reaches *every* resource either API plane exposes — even types nobody wrote a tool for yet. ## The tool surface **321 tools: 178 read-only · 143 writes · 38 destructive** — counted from the registry itself, not by hand. [`docs/tool-manifest.json`](docs/tool-manifest.json) is **generated from the live FastMCP registry** (`make tool-manifest`) and a CI gate fails the build if it ever drifts from the code. Per-tool descriptions, safety annotations, and parameters all live there; the narrative registry with slice tracking is [`docs/tool-catalog.md`](docs/tool-catalog.md). | Layer | What it does | Examples | |---|---|---| | **Discovery & schema** | Explore what any instance can do | `rancher_server_version`, `rancher_norman_schema_list`, `rancher_capability_domain_list` | | **Generic engine** | CRUD + actions + links + watch on *any* resource, both planes | `rancher_steve_resource_list`, `rancher_norman_resource_action_invoke`, `rancher_steve_resource_watch` | | **Curated reads** | Typed, shaped responses across ~25 domains | `rancher_pods_list`, `rancher_deployments_list`, `rancher_longhorn_volumes_list`, `rancher_policy_reports_list` | | **Curated writes** | Guarded mutations | `rancher_deployment_scale`, `rancher_deployment_restart`, `rancher_cron_job_suspend`, `rancher_node_cordon`, `rancher_secret_create` | | **Operator rollups** | One-call triage | `rancher_cluster_health_check`, `rancher_find_failing_pods`, `rancher_find_stalled_rollouts`, `rancher_project_health_summary` | Domains covered: clusters & nodes · projects & namespaces · workloads · pods & services · storage · networking · config & secrets *(values masked)* · certificates *(keys masked)* · RBAC · auth & identity · apps & catalogs · logging pipeline · Prometheus monitoring · policy reports · CIS compliance · backup operator · etcd backups · Longhorn · Fleet · provisioning · settings & features · alerts & notifiers. ## Quick start ### Requirements - Python 3.12+ and [uv](https://docs.astral.sh/uv/) - A Rancher API token ([creating one](https://ranchermanager.docs.rancher.com/reference-guides/user-settings/api-keys)) ### Install & run ```bash # From source git clone https://github.com/rex/mcp-rancher.git cd mcp-rancher make setup # deps, .env scaffold, pre-commit hooks cp .env.example .env # set RANCHER_URL + RANCHER_TOKEN make dev # run the MCP server (stdio) ``` Once published to PyPI, it's one line: `uvx rancher-mcp`. ### Claude Code ```bash claude mcp add rancher \ -e RANCHER_URL=https://rancher.example.com \ -e RANCHER_TOKEN=token-xxxxx:yyyyyyyyy \ -- uv run --directory /path/to/mcp-rancher rancher-mcp ``` ### Claude Desktop ```json { "mcpServers": { "rancher": { "command": "uv", "args": ["run", "--directory", "/path/to/mcp-rancher", "rancher-mcp"], "env": { "RANCHER_URL": "https://rancher.example.com", "RANCHER_TOKEN": "token-xxxxx:yyyyyyyyy" } } } } ``` ### Multiple instances ```env RANCHER_INSTANCES_JSON='{ "production": {"url": "https://rancher.prod.example.com", "token": "token-a:xxx", "verify_ssl": true, "read_only": true}, "lab": {"url": "https://rancher.lab.example.com", "token": "token-b:yyy", "verify_ssl": false, "read_only": false} }' RANCHER_DEFAULT_INSTANCE=production ``` Every tool takes an optional `instance` argument. Instances flagged `read_only: true` refuse **all** mutations at the settings layer. ## Architecture ```mermaid flowchart LR A[MCP client<br/>Claude Code · Claude Desktop · any] -- stdio --> S subgraph S[rancher-mcp] direction TB L1[Discovery & schema<br/>planes · schemas · capabilities] L2[Generic engine<br/>any resource · both planes<br/>CRUD · actions · links · watch] L3[Curated tools<br/>typed models · shaped output<br/>next-step hints] G[Safety layer<br/>read-only guard · confirmation phrases<br/>audit log · rate limit · masking] L1 --> L2 --> L3 L3 --> G L2 --> G end G -- Norman /v3 --> R1[(Rancher<br/>instance A)] G -- Steve /v1 + k8s proxy --> R1 G -- Norman + Steve --> R2[(Rancher<br/>instance B)] ``` Three layers, deliberately separate: **discovery** tells you what an instance can do, the **generic engine** can touch anything it exposes, and **curated tools** make the common paths typed, shaped, and self-describing (every response carries `suggested_next_steps`). Most curated tools are **generated from YAML descriptors** (`catalog/curated_tools/`) with a drift gate — the editorial decisions live in descriptors, not boilerplate. ## Safety model Built for the day an agent is pointed at the cluster that pays your salary: | Guard | Behavior | |---|---| | **Read-only instances** | `read_only: true` refuses every mutation for that instance, before tool logic runs | | **Destructive confirmation** | Deletes require an explicit typed phrase (e.g. `"delete steve namespace foo"`) — no phrase, no delete | | **Tool annotations** | Every tool declares `readOnlyHint` / `destructiveHint` / `idempotentHint`, so clients can gate UX on them | | **Audit log** | Every mutation emits a structured `event="audit"` record — tool, operation, plane, instance, resource, outcome. Argument *names* only; values never logged | | **Rate limiting** | Token-bucket on writes (default 60/min) — a runaway loop can't machine-gun your API | | **Secret & key masking** | Secret values and certificate private keys are structurally absent from curated responses (reveal is an explicit generic-tool opt-in) | | **Structured errors** | Guard rejections return typed `error_code` envelopes agents can branch on — never raw strings | ## Compatibility | | | |---|---| | **Primary target** | Rancher **2.9.3** (production-validated) | | **Compatibility floor** | Rancher **2.6.5** (kept green via capability detection) | | **API planes** | Norman `/v3` + Steve `/v1` (+ per-cluster Kubernetes proxy) | | **Transport** | stdio | Capability detection bridges version differences at runtime — no version-pinned builds, no "works on my Rancher." Both targets are exercised by the same test suite, and read paths have been validated live against both a 2.6.5 lab and a 2.9.3 production fleet ([validation report](docs/live-validation-2026-05-06.md)). ## Configuration | Variable | Default | Purpose | |---|---|---| | `RANCHER_URL` | — | Rancher server URL (single-instance mode) | | `RANCHER_TOKEN` | — | API token (`token-xxxxx:yyyyyyyyy`) | | `RANCHER_VERIFY_SSL` | `true` | TLS verification | | `RANCHER_INSTANCES_JSON` | — | Multi-instance config (see above) | | `RANCHER_DEFAULT_INSTANCE` | first defined | Instance used when a tool call names none | | `RANCHER_MCP_SERVER_NAME` | `rancher-mcp` | Server identity announced to clients | | `RANCHER_MCP_SERVER_DESCRIPTION` | built-in | Server description announced to clients | | `RANCHER_MCP_WRITE_RATE_LIMIT_PER_MIN` | `60` | Write rate limit (`0` disables) | ## Project status Shipping and stable for **read, triage, and guarded write** operations. Honest ledger of what's beyond that: - **Destructive workflows** (node drain, etcd/backup restore, cert rotation, cluster upgrade/delete) are **roadmap** — deliberately staged after real-world read-path mileage. The generic engine + confirmation guard already covers these cases for operators who need them today. - The Alertmanager routes/silences surface needs an in-cluster API integration and is deferred. - The full per-version compatibility matrix (Track G) is in progress; the [first live validation run](docs/live-validation-2026-05-06.md) covers the read matrix on both targets. Work is tracked to the tool level: [`docs/tool-catalog.md`](docs/tool-catalog.md) (every tool has a row, every gap a slice ID) and [`ROADMAP.md`](ROADMAP.md). ## Development ```bash make help # every target, documented make validate # codegen drift + manifest drift + architecture + lint + typecheck + tests make tool-manifest # regenerate docs/tool-manifest.json from the registry make lab-up # local Rancher 2.6.5 lab (kind + helm), fully scripted make integration-current # isolated Rancher 2.14.3 end-to-end test run make live-read-matrix # read-only validation probes against configured instances make mock-rancher # fixture-backed mock Rancher for provider-config testing ``` - **Local lab** — a self-contained Rancher 2.6.5 on kind with a simulated downstream cluster; repo-local kubeconfigs, never touches your machine state. - **Current integration lab** — Rancher 2.14.3 on separate Kind clusters and port `9443`; run it serially with `make integration-current` to avoid overlapping Docker resource demand with the legacy lab. - **Contract fixtures** — sanitized captures from live Rancher committed under `tests/fixtures/`; `respx` pins the HTTP boundary in tests. - **Codegen** — curated tools are emitted from `catalog/curated_tools/*.yml` descriptors; `make check-codegen` fails on drift. - **Gates** — ruff, pyright strict, 624 tests with coverage floor, architecture line-limits, module-shape checks, secret scanning. All fail closed, all wired into pre-commit. Stack: Python 3.12 · [FastMCP](https://github.com/modelcontextprotocol/python-sdk) · [httpx](https://www.python-httpx.org/) · [Pydantic v2](https://docs.pydantic.dev/) · [structlog](https://www.structlog.org/) · [uv](https://docs.astral.sh/uv/) ## Security See [SECURITY.md](SECURITY.md) for the threat model, token guidance, and how to report vulnerabilities. ## License [MIT](LICENSE)