Hook Endpoint

Airlock exposes a /hook endpoint for external tools that want a policy and approval decision without speaking MCP directly.

What it does

Non-MCP clients — CI scripts, Claude Code hooks, custom integrations — can POST a tool call description to Airlock and get back the same allow/deny/ask decision that MCP tool calls receive.

Request format

curl -X POST http://localhost:4111/hook \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $AIRLOCK_API_SECRET" \
  -d '{
    "client": "claude-code",
    "tool": "bash",
    "input": {
      "command": "git push origin main"
    }
  }'

Fields

Field	Required	Description
client	Yes	Client name (used for agent lookup if agent is not set)
agent	No	Explicit agent ID (overrides client)
tool	Yes	Tool name as the client knows it
input	No	Tool arguments (default {})
session_id	No	Optional session ID for tracking

Tool name normalization

Different clients call the same tools by different names. Airlock normalizes tool names across clients:

• Claude Code's bash → exec/run
• Other client-specific mappings are handled by the normalizer

The normalized name is what gets evaluated against the agent's policy.

Response flow

1. Airlock receives the request
2. The tool name is normalized based on the client
3. Policy is evaluated against the agent's allow/ask/deny lists
4. If allow: returns immediately with permission granted
5. If deny: returns immediately with permission denied
6. If ask: creates a HITL approval request, blocks until approved or denied, then returns the outcome

Authentication

If server.api_secret is configured, the endpoint requires Authorization: Bearer <secret>. The comparison uses timingSafeEqual — no timing side-channel.

server:
  api_secret: ${AIRLOCK_API_SECRET}

Use cases

Claude Code hooks

Use Claude Code's hook system to route tool calls through Airlock:

{
  "hooks": {
    "pre_tool_use": {
      "command": "curl -s -X POST http://localhost:4111/hook -H 'Content-Type: application/json' -d '{\"client\":\"claude-code\",\"tool\":\"$TOOL\",\"input\":$INPUT}'"
    }
  }
}

CI pipeline gates

Check if a deployment or sensitive operation is approved:

RESULT=$(curl -s -X POST http://localhost:4111/hook \
  -H "Authorization: Bearer $AIRLOCK_SECRET" \
  -H "Content-Type: application/json" \
  -d '{"client":"ci","agent":"deploy-bot","tool":"deploy/production","input":{"version":"v1.2.3"}}')

if echo "$RESULT" | jq -e '.allowed' > /dev/null; then
  echo "Approved — deploying"
else
  echo "Denied — aborting"
  exit 1
fi

Custom integrations

Any HTTP client can call the hook endpoint to get Airlock policy decisions without implementing MCP.