regex

Test/replace regex patterns (200 sats/call; free tier 100 calls/mo)

SERVERHyperion SOURCEhttps://hyperion.thetempleofdoom.com/mcp

Low RISK CLASS

Category Read

Parameters 42 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/com-thetempleofdoom-hyperion-hyperion/regex.md

WHAT IT DOES

What regex does on Hyperion

AI agents call regex to retrieve information from Hyperion without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Parameter	Type	Required	Description
`text`	string	Yes	Input text to search against.
`flags`	string	—	Flags like "g", "i", "m" (default "g").
`pattern`	string	Yes	Regex pattern string without slashes.
`replacement`	string	—	Optional replacement text string.

Parameters from the server's own tool schema.

RISK

Why regex is rated Low

Even though regex only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs regex safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Hyperion, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For regex, this is the rule to start with:

regex Allowed

regex is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "regex": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Hyperion, apply this rule, and every regex call is checked against it from then on.

FAQ

Questions about regex

What does the regex tool do? +

Test/replace regex patterns (200 sats/call; free tier 100 calls/mo). It is categorised as a Read tool in the Hyperion MCP Server, which means it retrieves data without modifying state.

What parameters does regex accept? +

regex accepts 4 parameters: text, flags, pattern, replacement. Required: text, pattern. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on regex? +

Register the Hyperion MCP server in PolicyLayer and add a rule for regex: 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 Hyperion. Nothing to install.

What risk level is regex? +

regex is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit regex? +

Yes. Add a rate_limit block to the regex 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.

How do I block regex completely? +

Set action: deny in the PolicyLayer policy for regex. 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.

What MCP server provides regex? +

regex is provided by the Hyperion MCP server (https://hyperion.thetempleofdoom.com/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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