wasm_diff

SERVERJshookmcp SOURCE@jshookmcp/jshook

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-vmoranv-jshookmcp/wasm-diff.md

WHAT IT DOES

What wasm_diff does on Jshookmcp

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

RISK

Why wasm_diff is rated Low

Tool analyzes and compares WebAssembly binaries for research; produces read-only diffs without side effects.

From the tool's definition disassembles, emits diff, writes to artifact; no modification of binaries or systems

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs wasm_diff safely

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

wasm_diff Allowed

wasm_diff 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": {
    "wasm_diff": {}
  }
}

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

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

FAQ

Questions about wasm_diff

What does the wasm_diff tool do? +

Patch-diff two .wasm binaries (original vs. patched) for vulnerability research: disassembles both via wasm2wat and emits a structured function-level diff (added/removed/changed) plus a per-function WAT line-level unified diff. The full diff is written to an artifact; the response carries summaries and previews. It is categorised as a Read tool in the Jshookmcp MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on wasm_diff? +

Register the Jshook MCP server in PolicyLayer and add a rule for wasm_diff: 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 Jshookmcp. Nothing to install.

What risk level is wasm_diff? +

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

Can I rate-limit wasm_diff? +

Yes. Add a rate_limit block to the wasm_diff 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 wasm_diff completely? +

Set action: deny in the PolicyLayer policy for wasm_diff. 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 wasm_diff? +

wasm_diff is provided by the Jshook MCP server (@jshookmcp/jshook). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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