Ambassador (Emissary-Ingress) Skill

Manage Ambassador/Emissary-Ingress mappings, hosts, TLS, auth filters, and rate limiting.

Core Helper Functions

#!/bin/bash

AMBASSADOR_NS="${AMBASSADOR_NAMESPACE:-ambassador}"

# Get Ambassador CRDs via kubectl
amb_get() {
    local resource="$1" ns="${2:---all-namespaces}"
    if [ "$ns" = "--all-namespaces" ]; then
        kubectl get "$resource" -A -o json 2>/dev/null
    else
        kubectl get "$resource" -n "$ns" -o json 2>/dev/null
    fi
}

# Ambassador diagnostics
amb_diag() {
    local pod
    pod=$(kubectl get pods -n "$AMBASSADOR_NS" -l app.kubernetes.io/name=emissary-ingress -o jsonpath='{.items[0].metadata.name}' 2>/dev/null)
    kubectl exec -n "$AMBASSADOR_NS" "$pod" -- curl -s "http://localhost:8877/$1" 2>/dev/null
}

MANDATORY: Discovery-First Pattern

Phase 1: Discovery

#!/bin/bash

echo "=== Ambassador Pods ==="
kubectl get pods -n "$AMBASSADOR_NS" -l app.kubernetes.io/name=emissary-ingress -o json 2>/dev/null | jq -r '
    .items[] | "\(.metadata.name)\t\(.status.phase)\tRestarts: \(.status.containerStatuses[0].restartCount // 0)\tVersion: \(.spec.containers[0].image | split(":") | last)"
' | column -t

echo ""
echo "=== Mappings ==="
amb_get mappings | jq -r '
    .items[] | "\(.metadata.name)\t\(.metadata.namespace)\t\(.spec.prefix // .spec.hostname // "*")\t->\t\(.spec.service)\t\(.spec.rewrite // "/")"
' | column -t | head -20

echo ""
echo "=== Hosts ==="
amb_get hosts | jq -r '
    .items[] | "\(.metadata.name)\t\(.spec.hostname)\t\(.spec.tlsSecret.name // "no-tls")\t\(.status.state // "n/a")"
' | column -t | head -15

echo ""
echo "=== TLS Contexts ==="
amb_get tlscontexts | jq -r '
    .items[]? | "\(.metadata.name)\t\(.metadata.namespace)\t\(.spec.hosts | join(",") // "all")\t\(.spec.secret // "n/a")"
' | column -t | head -10

echo ""
echo "=== Listeners ==="
amb_get listeners "$AMBASSADOR_NS" | jq -r '
    .items[]? | "\(.metadata.name)\t\(.spec.port)\t\(.spec.protocol)\t\(.spec.securityModel)"
' | column -t | head -10

echo ""
echo "=== Auth Services ==="
amb_get authservices | jq -r '
    .items[]? | "\(.metadata.name)\t\(.spec.auth_service)\t\(.spec.proto // "http")"
' | column -t | head -10

Phase 2: Analysis

#!/bin/bash
MAPPING="${1:?Mapping name required}"
NS="${2:-default}"

echo "=== Mapping Configuration ==="
amb_get mappings "$NS" | jq --arg name "$MAPPING" '
    .items[] | select(.metadata.name == $name) | {
        name: .metadata.name, prefix: .spec.prefix,
        service: .spec.service, rewrite: .spec.rewrite,
        host: .spec.host, hostname: .spec.hostname,
        timeout_ms: .spec.timeout_ms, retries: .spec.retry_policy,
        headers: .spec.headers, cors: .spec.cors,
        weight: .spec.weight, labels: .spec.labels
    }'

echo ""
echo "=== Diagnostics Overview ==="
amb_diag "ambassador/v0/diag/?json=true" | jq '{
    system: .system,
    envoy_status: .envoy_status,
    cluster_count: (.clusters | length),
    route_count: (.routes | length)
}' 2>/dev/null

echo ""
echo "=== Route Table ==="
amb_diag "ambassador/v0/diag/?json=true" | jq -r '
    .routes[:15][] | "\(.prefix // .regex // "*")\t\(.clusters[0].name // "n/a")\t\(.headers // [])"
' | column -t 2>/dev/null | head -15

echo ""
echo "=== Envoy Cluster Health ==="
amb_diag "ambassador/v0/diag/?json=true" | jq -r '
    .clusters[:10][] | "\(.name)\t\(.healthy_members // 0)/\(.num_members // 0) healthy"
' | column -t 2>/dev/null | head -10

Output Rules

• TOKEN EFFICIENCY: Target <=50 lines per output
• Show mapping prefix -> service relationships clearly
• Include relevant Ambassador CRD API version (v2 vs v3alpha1)

Safety Rules

• Read-only by default: Use get/describe and diagnostics for inspection
• Mapping changes affect routing immediately after Envoy config reload
• Host changes can disrupt TLS termination
• Auth service changes can lock out all API consumers

Output Format

Present results as a structured report:

Managing Ambassador Report
══════════════════════════
Resources discovered: [count]

Resource       Status    Key Metric    Issues
──────────────────────────────────────────────
[name]         [ok/warn] [value]       [findings]

Summary: [total] resources | [ok] healthy | [warn] warnings | [crit] critical
Action Items: [list of prioritized findings]

Target ≤50 lines of output. Use tables for multi-resource comparisons.

Anti-Hallucination Rules

1. NEVER assume resource names — always discover via CLI/API in Phase 1 before referencing in Phase 2.
2. NEVER fabricate metric names or dimensions — verify against the service documentation or --help output.
3. NEVER mix CLI commands between service versions — confirm which version/API you are targeting.
4. ALWAYS use the discovery → verify → analyze chain — every resource referenced must have been discovered first.
5. ALWAYS handle empty results gracefully — an empty response is valid data, not an error to retry.

Counter-Rationalizations

Shortcut	Counter	Why
"I'll skip discovery and check known resources"	Always run Phase 1 discovery first	Resource names change, new resources appear — assumed names cause errors
"The user only asked for a quick check"	Follow the full discovery → analysis flow	Quick checks miss critical issues; structured analysis catches silent failures
"Default configuration is probably fine"	Audit configuration explicitly	Defaults often leave logging, security, and optimization features disabled
"Metrics aren't needed for this"	Always check relevant metrics when available	API/CLI responses show current state; metrics reveal trends and intermittent issues
"I don't have access to that"	Try the command and report the actual error	Assumed permission failures prevent useful investigation; actual errors are informative

Common Pitfalls

• CRD versions: v2 (getambassador.io/v2) vs v3alpha1 (getambassador.io/v3alpha1) have different fields
• Mapping precedence: Longer prefix matches win; use weight for same-prefix disambiguation
• Rewrite default: Default rewrite is /; set rewrite: "" to preserve original path
• Host binding: Mappings must be bound to Hosts via hostname field in v3
• Diagnostics port: 8877 is for diagnostics; do not expose externally