Mirrord Configuration Skill

Purpose

Generate and validate mirrord.json configuration files:

• Generate valid configs from natural language descriptions
• Validate user-provided configs against schema
• Fix invalid configurations with explanations
• Explain configuration options and patterns

Critical First Steps

Step 1: Load references Use the view tool to read BOTH reference files:

1. /mnt/skills/user/mirrord/references/schema.json - Authoritative JSON Schema
2. /mnt/skills/user/mirrord/references/configuration.md - Configuration reference

Step 2: Install mirrord CLI (if not present)

# Check if installed
which mirrord || brew install metalbear-co/mirrord/mirrord || curl -fsSL https://raw.githubusercontent.com/metalbear-co/mirrord/main/scripts/install.sh | bash

Step 3: Validate before presenting After generating any config, ALWAYS run:

mirrord verify-config /path/to/config.json

• If validation fails, fix the config and re-validate
• Only present configs that pass validation
• Include validation output in your response

Request Types

Generate new config

User describes what they want without providing JSON.

• Extract target (pod/deployment), namespace, features needed
• Create minimal valid config using only schema-defined keys
• Default to minimal configs; mirrord has sensible defaults

Validate existing config

User provides JSON to check.

• Parse strictly (catch trailing commas, comments, invalid syntax)
• Validate against schema
• List issues by severity: Errors → Warnings → Suggestions
• Provide corrected version

Modify existing config

User wants changes to their config.

• Validate first, then apply requested changes
• Ensure modifications maintain schema conformance

Response Format

For generation or fixes:

1. Brief summary (1-2 sentences)
2. Valid JSON config in code block
3. Validation output from mirrord verify-config:

{
  "type": "Success",
  "warnings": [],
  "compatible_target_types": [...]
}

4. Short explanation of key sections (if validation passed)

For validation:

1. Errors (schema violations - will cause failures)
2. Warnings (valid but potentially wrong behavior)
3. Suggestions (optional improvements)
4. Corrected JSON config

Configuration Guidelines

Common patterns (verify exact keys in schema):

Target selection:

• "target": "pod/name" or {"path": "pod/name", "namespace": "staging"}
• Set operator if using operator mode
• Specify kube_context if needed

Features:

• "env": true - Mirror environment variables
• "env": {"include": "VAR1;VAR2"} - Selective inclusion
• "fs": "read" - Read-only filesystem access
• "network": true - Enable network mirroring
• "network": {"incoming": {"mode": "steal"}} - Steal incoming traffic

Network modes:

• Check schema for valid incoming.mode values (e.g., "steal", "mirror", "off")
• Configure HTTP filters, port mapping, localhost handling

Templating:

• mirrord uses Tera templates
• Example: "target": "{{ get_env(name=\"TARGET\", default=\"pod/fallback\") }}"
• Templates must remain valid JSON

Validation Rules

Must enforce:

• Strict JSON parsing (no comments, no trailing commas)
• All keys must exist in schema
• Correct types (string vs object, enums, etc.)
• Required fields present
• No additionalProperties where schema forbids them

Path notation for errors: Use JSON Pointer style: /feature/network/incoming/mode

Common Pitfalls

• User pastes YAML/TOML → Explain JSON required, offer to convert structure
• User requests unsupported key → Say it's not in schema, suggest alternatives
• Overly complex configs → Prefer minimal configs with only requested settings
• Conflicting settings → Identify based on configuration.md semantics

What to Ask (only if critical)

If request is under-specified, ask for ONE detail:

• Target identity (pod name, namespace)
• Incoming network behavior (steal vs mirror)
• Operator usage (yes/no)
• Specific ports to map/ignore

Otherwise provide safe defaults and note assumptions.

Automatic Validation Workflow

Every generated or modified config MUST be validated before presentation:

1. Save config to temporary file
2. Run mirrord verify-config <file>
3. If validation fails:
   • Parse error messages
   • Fix the config
   • Re-validate until success
4. Present config with validation output

Never skip validation - it catches schema errors we might miss manually.

Quality Requirements

✓ Schema-first: Output must conform to schema.json
✓ No hallucination: Only use documented keys
✓ Valid JSON: Always parseable, no comments
✓ Actionable feedback: Clear explanations of what to fix and why
✓ Minimal configs: Don't set unnecessary options

Example Scenarios

"Connect to pod api-7c8d9 in staging, steal traffic on port 8080, exclude secret env vars" → Read references, generate minimal config with target, network.incoming, env.exclude

User provides invalid JSON with trailing comma → Parse error → Fix syntax → Validate against schema → Explain issues → Provide corrected config

"Is my config valid?" + JSON provided → Check syntax → Validate all keys/types against schema → List violations → Suggest fixes