Bulk regex find-and-replace across files. Dry-run by default — first call shows preview, second call with dry_run=false applies. Use for mechanical changes like adding async/await, renaming patterns, updating imports across many files. Potentially destructive — can modify or delete code. Always p...
AI agents call apply_codemod to permanently remove resources in Trace — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
This tool performs bulk code modifications across many files simultaneously. While it has a dry-run safeguard, when applied it can irreversibly overwrite or delete code across the entire codebase.
From the tool's definition Potentially destructive — can modify or delete code. Bulk regex find-and-replace across files. second call with dry_run=false applies.
Documented attack patterns abuse exactly the kind of access apply_codemod gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Trace, and nothing reaches the server without passing your rules. This is the rule we recommend for apply_codemod:
{
"version": "1",
"default": "deny",
"hide": [
"apply_codemod"
]
}apply_codemod disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.
Free to start. No card required.
Bulk regex find-and-replace across files. Dry-run by default — first call shows preview, second call with dry_run=false applies. Use for mechanical changes like adding async/await, renaming patterns, updating imports across many files. Potentially destructive — can modify or delete code. Always preview with dry_run=true first. Returns JSON: { success, matchedFiles, changes: [{ file, matches }], applied }. It is categorised as a Destructive tool in the Trace MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Trace MCP server in PolicyLayer and add a rule for apply_codemod: 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 Trace. Nothing to install.
apply_codemod is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the apply_codemod 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_codemod. 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_codemod is provided by the Trace MCP server (nikolai-vysotskyi/trace-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 178 Trace tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
178 Trace tools catalogued and risk-classified — across an index of 42,500+ MCP servers.