Auto-detect and run tests in a local development environment
AI agents invoke local_dev_run_tests to trigger actions in Mcp Local Dev. 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.
local_dev_run_tests triggers real processes with real consequences. An agent gone sideways doesn't fire it once — it starts dozens of builds, sends mass notifications, or burns through compute before anyone looks up.
Documented attack patterns abuse exactly the kind of access local_dev_run_tests gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mcp Local Dev, and nothing reaches the server without passing your rules. This is the rule we recommend for local_dev_run_tests:
{
"version": "1",
"default": "deny",
"tools": {
"local_dev_run_tests": {
"limits": [
{
"counter": "local_dev_run_tests_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}local_dev_run_tests 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.
Auto-detect and run tests in a local development environment. It is categorised as a Execute tool in the Mcp Local Dev MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Mcp Local Dev MCP server in PolicyLayer and add a rule for local_dev_run_tests: 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 Mcp Local Dev. Nothing to install.
local_dev_run_tests 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 local_dev_run_tests 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 local_dev_run_tests. 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.
local_dev_run_tests is provided by the Mcp Local Dev MCP server (txbm/mcp-local-dev). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 4 Mcp Local Dev tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4 Mcp Local Dev tools catalogued and risk-classified — across an index of 42,500+ MCP servers.