Applies a SQL migration to the database. SQL passed to this tool will be tracked within the database, so LLMs should use this for DDL operations (schema changes).
Part of the Supabase server.
Free to start. No card required.
AI agents use apply_migration to create or modify resources in Supabase. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call apply_migration repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Supabase.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"apply_migration": {
"limits": [
{
"counter": "apply_migration_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Supabase policy for all 32 tools.
These attack patterns abuse exactly the kind of access apply_migration gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Applies a SQL migration to the database. SQL passed to this tool will be tracked within the database, so LLMs should use this for DDL operations (schema changes).. It is categorised as a Write tool in the Supabase MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Supabase MCP server in PolicyLayer and add a rule for apply_migration: 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 Supabase. Nothing to install.
apply_migration is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the apply_migration 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 apply_migration. 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.
apply_migration is provided by the Supabase MCP server (@modelcontextprotocol/server-supabase). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 32 Supabase tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.