Evaluate an expression in the current frame context (e.g. print a variable, call a method).
AI agents invoke bazel_ios_lldb_expression to trigger actions in XcodeBazelMCP. 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.
This tool executes arbitrary expressions via LLDB in the context of a running process. It can call methods, access memory, and execute code at runtime. This is an Execute-category tool because it runs code/expressions in a live debug session. Severity is high because arbitrary code execution in a running process could have significant side effects depending on what expressions are evaluated.
From the tool's definition Evaluate an expression in the current frame context (e.g. print a variable, call a method)
Documented attack patterns abuse exactly the kind of access bazel_ios_lldb_expression gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and XcodeBazelMCP, and nothing reaches the server without passing your rules. This is the rule we recommend for bazel_ios_lldb_expression:
{
"version": "1",
"default": "deny",
"tools": {
"bazel_ios_lldb_expression": {
"limits": [
{
"counter": "bazel_ios_lldb_expression_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}bazel_ios_lldb_expression 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.
Evaluate an expression in the current frame context (e.g. print a variable, call a method). It is categorised as a Execute tool in the XcodeBazelMCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the XcodeBazel MCP server in PolicyLayer and add a rule for bazel_ios_lldb_expression: 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 XcodeBazelMCP. Nothing to install.
bazel_ios_lldb_expression 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 bazel_ios_lldb_expression 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 bazel_ios_lldb_expression. 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.
bazel_ios_lldb_expression is provided by the XcodeBazel MCP server (xcodebazelmcp/xcodebazelmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from XcodeBazelMCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
117 XcodeBazelMCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.