Rename a symbol across all usages (definition + all importing files). Runs collision detection first and aborts on conflicts. Dry-run by default — preview the plan, then re-call with dry_run: false to apply. Returns the list of edits applied. Modifies source files when dry_run is false. Use check...
AI agents use apply_rename to create or update resources in Trace — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Trace environment.
apply_rename performs reversible changes to source code by renaming symbols across multiple files. While it offers a dry-run mode and collision detection for safety, when executed (dry_run: false), it modifies source files. This is a Write operation rather than Destructive because renames are reversible—the original names can be renamed back.
From the tool's definition The tool description explicitly states: 'Modifies source files when dry_run is false' and 'Rename a symbol across all usages (definition + all importing files)'. This is a multi-file modification operation.
Documented attack patterns abuse exactly the kind of access apply_rename 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_rename:
{
"version": "1",
"default": "deny",
"tools": {
"apply_rename": {
"limits": [
{
"counter": "apply_rename_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}apply_rename stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
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Rename a symbol across all usages (definition + all importing files). Runs collision detection first and aborts on conflicts. Dry-run by default — preview the plan, then re-call with dry_run: false to apply. Returns the list of edits applied. Modifies source files when dry_run is false. Use check_rename first to verify safety; use plan_refactoring with type=. It is categorised as a Write tool in the Trace MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Trace MCP server in PolicyLayer and add a rule for apply_rename: 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_rename 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_rename 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_rename. 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_rename 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.