Merges migrations and edge functions from a development branch to production.
AI agents invoke merge_branch to trigger actions in PostgREST. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.
Merging to production triggers schema migrations and code deployments that modify the live production environment. This is an irreversible or difficult-to-reverse operation with high blast radius — bad migrations can corrupt data or break production.
From the tool's definition Merges migrations and edge functions from a development branch to production
Documented attack patterns abuse exactly the kind of access merge_branch gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and PostgREST, and nothing reaches the server without passing your rules. This is the rule we recommend for merge_branch:
{
"version": "1",
"default": "deny",
"tools": {
"merge_branch": {
"limits": [
{
"counter": "merge_branch_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}merge_branch stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Merges migrations and edge functions from a development branch to production. It is categorised as a Execute tool in the PostgREST MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the PostgREST MCP server in PolicyLayer and add a rule for merge_branch: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches PostgREST. Nothing to install.
merge_branch is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the merge_branch rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for merge_branch. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
merge_branch is provided by the PostgREST MCP server (supabase/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 32 PostgREST tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
32 PostgREST tools catalogued and risk-classified — across an index of 42,500+ MCP servers.