replace_function
Replace a function to always return a specific value.
This record as markdown: /tools/0xhackerfren-frida-game-hacking-mcp/replace-function.md
What replace_function does on Frida Game Hacking MCP
AI agents invoke replace_function to trigger actions in Frida Game Hacking MCP. 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.
Why replace_function is rated High
Replacing a function in a running process is a form of code injection/hooking that modifies execution flow. It is not merely writing data but actively altering how code executes in a target process. This falls under Execute (code injection/dynamic instrumentation), with high severity due to the potential for abuse across arbitrary processes including games or other applications.
From the tool's definition Replace a function to always return a specific value — this injects code into a running process to intercept and override function behavior
Attacks that exploit this kind of access
The rule that runs replace_function safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Frida Game Hacking MCP, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For replace_function, this is the rule to start with:
replace_function 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.
The button opens the PolicyLayer dashboard: create your workspace, connect Frida Game Hacking MCP, apply this rule, and every replace_function call is checked against it from then on.
Questions about replace_function
Replace a function to always return a specific value. It is categorised as a Execute tool in the Frida Game Hacking MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Frida Game Hacking MCP server in PolicyLayer and add a rule for replace_function: 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 Frida Game Hacking MCP. Nothing to install.
replace_function 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 replace_function 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 replace_function. 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.
replace_function is provided by the Frida Game Hacking MCP server (0xhackerfren/frida-game-hacking-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on Frida Game Hacking, and thousands of servers like it.
Across the catalogue