# Mirrord Propagation Discovery

Scans a live Kubernetes environment with `mirrord dump` to find an identifier mirrord...

- Repository: https://github.com/metalbear-co/mirrord (5397 stars)
- Category: DevOps
- License: MIT
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add metalbear-co/mirrord --skill mirrord-propagation-discovery -g -a claude-code -y`
Codex: `npx skills add metalbear-co/mirrord --skill mirrord-propagation-discovery -g -a codex -y`
Cursor: `npx skills add metalbear-co/mirrord --skill mirrord-propagation-discovery -g -a cursor -y`
Gemini CLI: `npx skills add metalbear-co/mirrord --skill mirrord-propagation-discovery -g -a gemini-cli -y`

## Description

Scans a live Kubernetes environment with `mirrord dump` to find an identifier mirrord can filter traffic on: a header, a `baggage` or `tracestate` member, a tenant or user id, a trace id (W3C, B3, X-Ray, Google, Jaeger), a JWT claim, a cookie, a path segment, or a JSON body field that is present on every hop of a request chain, unique to one developer's traffic, and settable by that developer. Runs mirror-only dumps on each service, sends a tagged probe request at the edge or observes real traffic, scores the candidates, and produces the matching `http_filter` (regex, jq on headers, path, method, body, or combinations) plus a per-hop report of where each identifier is dropped. Installs the mirrord CLI through a package manager when it is missing. Use when the user asks what to filter on, whether the cluster already propagates a request id or trace context, how to isolate their own requests on a shared staging cluster, how to filter on a JWT or cookie with mirrord, or wants to inspect live traffic with mirrord dump. Changes no application code: propagation gaps go to the mirrord-header-propagation skill.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# mirrord Propagation Discovery Skill

> mirrord routes a request to a developer's local process when the request matches an HTTP filter. On a shared cluster that filter has to pick out **one developer's requests at every service the request passes through**, so the value it matches on must already travel with the request across all hops. This skill finds that value in a live environment instead of assuming one: it dumps the traffic arriving at each service with `mirrord dump`, checks which identifiers survive from the edge to the last hop, and turns the best one into a `mirrord.json` filter. The sister skill `mirrord-header-propagation` changes code to make `baggage` propagate; this one changes nothing and tells you what already works.

## Security Boundaries

> **IMPORTANT:** Follow these rules for all operations in this skill.

The rest: https://github.com/metalbear-co/mirrord/blob/HEAD/mirrord/mcp/corpus/skills/mirrord-propagation-discovery/SKILL.md