AI agents use write_tests to create or update resources in Proxima — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Proxima environment.
The name strongly suggests writing test files or test code, which is a reversible Write operation. Without a description, confidence is reduced. Severity is medium because creating test code has limited blast radius compared to modifying production data, though incorrect tests could mask bugs.
From the tool's definition Tool name 'write_tests' indicates creation of test code/files. Description is empty, limiting precision.
Documented attack patterns abuse exactly the kind of access write_tests gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Proxima, and nothing reaches the server without passing your rules. This is the rule we recommend for write_tests:
{
"version": "1",
"default": "deny",
"tools": {
"write_tests": {
"limits": [
{
"counter": "write_tests_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}write_tests 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.
Free to start. No card required.
write_tests. It is categorised as a Write tool in the Proxima MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Proxima MCP server in PolicyLayer and add a rule for write_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 Proxima. Nothing to install.
write_tests 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 write_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 write_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.
write_tests is provided by the Proxima MCP server (zen4-bit/proxima). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 50 Proxima tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
50 Proxima tools catalogued and risk-classified — across an index of 42,500+ MCP servers.