AI agents write code that compiles, runs locally, and breaks the first time it touches your Kubernetes cluster. The cluster is full of state the model never sees: the env vars on the running pod, the schema in your real Postgres, the headers your upstream auth-service sends, the topics your consumer subscribes to. Without that context, the code an agent writes for your live infrastructure is informed guessing, whether you’re shipping a new feature or fixing a regression.
mirrord closes that gap. It runs a local process as if it were a real pod inside your cluster: real env vars, real DNS, real network, optionally real inbound traffic. A real example: Daylight Security pairs Cursor with mirrord for daily development. Their team cut their typical edit-test cycle from 5–8 minutes to about 5 seconds. The reason isn’t faster CPUs; it’s that the agent now operates against the real cluster the way a senior engineer would, instead of guessing from logs.
We recently shipped six Agent Skills that teach AI agents how and when to use mirrord. The whole bundle installs in one command.
# Claude Code
/plugin marketplace add metalbear-co/skills
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# Any Agent Skills consumer
npx skills add metalbear-co/skills
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Here’s what each skill does, with a concrete prompt that triggers it.
1. mirrord-quickstart
Zero-to-first-session for engineers (and agents) who have never used mirrord. Detects your OS, walks through CLI install or VS Code / IntelliJ setup, finds your target pod in the cluster, runs your first session. Your local process can now reach every service, database, and queue in the cluster.
Try: “I’m new to mirrord, help me run my Node app against my staging cluster.”
The agent installs mirrord, lists targets in your namespace, picks a likely match, and runs mirrord exec –target … — node server.js. No copy-paste from docs.
2. mirrord-config
Generates and validates mirrord.json, which tells mirrord what to do and where to do it. mirrord’s config surface is wide: traffic stealing vs mirroring, filesystem modes, env injection, target selection, database and queue behavior. The skill turns “I want X behavior” into valid config without you opening the docs.
Try: “Steal traffic from pod/api-server, but only requests carrying my baggage header so I don’t break anyone else’s session.”
The agent writes the right config, validates it against the schema, and explains what it does. The interesting part: the skill covers the full mirrord.json surface (target selection, traffic modes, env injection, file system hooks), not just filters. Filtered steal is one of the things that lets multiple developers share one cluster without colliding, but it’s only one of the patterns mirrord-config knows how to set up.
3. mirrord-operator
Sets up the mirrord Operator for teams. Mirroring traffic from a pod is concurrency-safe out of the box; you only need the operator when multiple developers want to steal the same pod’s traffic with different filters, share branched databases, or split a Kafka topic. The operator brokers session boundaries, RBAC, and the routing rules that make those interactions work without collisions.
Try: “Install the operator on our EKS cluster and configure RBAC so only the dev group can use it.”
monday.com runs 350+ engineers on a single shared staging cluster this way. The operator is what makes that scale work: concurrent filtered steal so multiple devs share one pod, queue splitting so they share one SQS topic, DB branching so they share one database, RBAC so they don’t touch workloads they shouldn’t, and the rest of the routing rules that let 350 developers work on the same cluster at the same time.
4. mirrord-ci
Run integration tests in CI in isolation against your staging cluster, instead of spinning up an ephemeral test environment for each PR. The service under test runs in the CI runner with mirrord; mirrord steals the cluster traffic destined for it and routes it to your build, so test traffic follows the same path it would in production, with only that one service swapped. That catches the integration bugs mocks miss, with one shared staging cluster instead of one ephemeral cluster per PR.
Try: “Set up GitHub Actions to run our integration tests against the staging cluster.”
The agent writes the workflow, injects your kubeconfig from a secret, sets MIRRORD_CI_API_KEY, and wires mirrord ci start around your service and mirrord ci stop in the cleanup hook.
5. mirrord-db-branching
Per-developer database branches. Copy-on-write Postgres (or any supported DB), so two engineers can develop against “the same” database without stepping on each other’s writes.
Try: “Give me an isolated DB branch off the staging Postgres for this feature.”
The agent provisions the branch via the operator, points your local process at the branch, and tears down when the session ends. No more “who deleted the test users?” Slack threads.
6. mirrord-kafka
Kafka queue splitting. Each developer gets a slice of the topic that only they consume, while the original consumer keeps running in the cluster. Lets you run a real Kafka workload locally without intercepting messages other people care about.
Try: “Set up queue splitting on the orders.created topic for my local consumer.”
The agent configures the operator’s Kafka splitter, gives your local process a per-developer consumer group, and confirms message routing.
Install
# Claude Code
/plugin marketplace add metalbear-co/skills
# Any Agent Skills consumer
npx skills add metalbear-co/skills
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Repo: github.com/metalbear-co/skills. Issues and PRs welcome; we ship updates fast.
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