Recipes

Guard code merges

For an agent that merges pull requests, in 15 frameworks.

Last reviewed 2026-10-02

Merges into feature branches run; merges into main wait for a person.

The rule

{
  "name": "code-merge-guard",
  "effect": "require_approval",
  "priority": 10,
  "match_path": "/tools/merge_pull_request",
  "conditions": [
    {
      "field": "base",
      "op": "eq",
      "value": "main"
    }
  ]
}

Measured on production (2026-10-02, rule tester): the risky call below matches this rule and the safe one does not.

Risky	`{"repo": "acme/app", "number": 812, "base": "main"}`
Safe	`{"repo": "acme/app", "number": 812, "base": "feature/login"}`

Pick your framework

Framework	Tool name CAIN sees	Plugs into
Python (any function)	`merge_pull_request`	the function that acts
LangChain	`merge_pull_request`	your agent's tool list
LangGraph	`merge_pull_request`	the tools your graph's nodes call
OpenAI Agents SDK	`merge_pull_request`	function tools
CrewAI	`merge_pull_request`	CrewAI's before-tool-call hooks
LlamaIndex	`merge_pull_request`	FunctionTool
Pydantic AI	`merge_pull_request`	an agent capability
AutoGen (agentchat)	`merge_pull_request`	the callables you give AssistantAgent
Google ADK	`merge_pull_request`	the functions in an agent's tools
Claude Agent SDK	`mcp__ops__merge_pull_request`	PreToolUse hooks
MCP client (Python)	`merge_pull_request`	any MCP client session
OpenTelemetry	`merge_pull_request`	your existing tracing
Any other framework	`merge_pull_request`	any Python callable
TypeScript / JavaScript	`merge_pull_request`	any async function
HTTP (any language)	`merge_pull_request`	your own call site

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