noor202401938-netizen · Sep 26, 2026 · Sep 26, 2026 · Sep 26, 2026 · Sep 27, 2026 · Sep 29, 2026
diff --git a/docs/integrations/mcp.mdx b/docs/integrations/mcp.mdx
@@ -22,10 +22,17 @@ Create the directory if it does not exist, then write the file:
 mkdir -p ~/.strix
 ```
 
-Paste the servers you want into `~/.strix/mcp-servers.json`. The example below shows one of each transport: a local filesystem server over `stdio` and a remote GitHub server over `http` with a bearer token:
+Paste the servers you want into `~/.strix/mcp-servers.json`. The example below shows local `stdio` servers (CyberChef for payload deobfuscation and a local filesystem server) alongside a remote GitHub server over `http` with a bearer token:
 
 ```json
 [
+  {
+    "name": "cyberchef",
+    "transport": "stdio",
+    "command": "npx",
+    "args": ["-y", "@noorfatima123456/cyber-chef-mcp"],
+    "notes": "CyberChef MCP server for multi-layer payload deobfuscation, crypto decoding, and entropy analysis."
+  },
   {
     "name": "local_fs",
     "transport": "stdio",

diff --git a/strix/skills/tooling/cyberchef.md b/strix/skills/tooling/cyberchef.md
@@ -0,0 +1,143 @@
+---
+name: cyberchef
+description: Multi-layer payload deobfuscation, cryptographic decoding, heuristic recipe detection (magic), and entropy analysis via CyberChef MCP.
+---
+
+# CyberChef MCP Tooling Playbook
+
+Official resources:
+- https://github.com/gchq/CyberChef
+- https://github.com/noor202401938-netizen/cyber-chef-mcp
+- https://gchq.github.io/CyberChef/
+- https://modelcontextprotocol.io
+
+CyberChef MCP provides 28 core data transformation, cryptographic, and forensic operations with zero external dependencies. Connected via the Model Context Protocol (MCP) server `cyberchef`, it enables Strix agents to autonomously analyze, deobfuscate, unpack, and verify encoded exploit payloads, authorization tokens, and obfuscated attack vectors with deterministic sub-millisecond execution.
+
+## MCP Discovery & Dispatch Workflow
+
+In Strix, agents interact with external MCP servers through the standard generic-dispatch tools:
+1. **Discover Connection**: Call `list_mcps()` to verify that the `cyberchef` connection is active.
+2. **Search Tools**: Call `search_mcp_tools(connection="cyberchef", query="magic")` to locate matching tool names.
+3. **Inspect Schema**: Call `get_mcp_tool_schema(connection="cyberchef", tool="cyberchef_magic")` to review argument parameters.
+4. **Dispatch Call**: Call `call_mcp(connection="cyberchef", tool="<tool_name>", arguments={...})` to execute the operation.
+
+## High-Signal CyberChef Tools
+
+When connected to `cyberchef`, the following tools are available on the connection:
+
+- `cyberchef_magic`: Run heuristic detection across known encodings, ciphers, and hash formats. Returns recommended deobfuscation recipes and confidence scores.
+- `cyberchef_bake`: Execute sequential operation chains (e.g. `[{"op": "From Base64"}, {"op": "URL Decode"}]`).
+- `cyberchef_from_base64`: Decode standard or URL-safe Base64 strings.
+- `cyberchef_to_base64`: Encode plaintext into Base64 / URL-safe Base64.
+- `cyberchef_from_hex`: Convert hexadecimal sequences to text (supports `None`, `Space`, `0x`, `Comma` delimiters).
+- `cyberchef_url_decode`: Decode single or multi-round percent-encoded parameters.
+- `cyberchef_rot13`: Rotate characters by offset (default 13, Caesar cipher support).
+- `cyberchef_xor`: Decrypt or apply bitwise XOR with secret key.
+- `cyberchef_jwt_decode`: Parse and inspect header, claims, alg, and signatures of JSON Web Tokens.
+- `cyberchef_entropy`: Calculate Shannon entropy to distinguish plaintext, compressed data, and encrypted or packed payloads.
+- `cyberchef_defang_url`: Defang malicious or suspicious indicators (`hxxps://target[.]com`) for safe reporting.
+- `cyberchef_extract_entities`: Extract URLs, IP addresses, and email addresses from raw logs or memory strings.
+
+## Agent-Safe Baseline for Automation
+
+### 1. Heuristic First (`cyberchef_magic`)
+Always run `cyberchef_magic` via `call_mcp` on unknown high-entropy or encoded strings before guessing transformations:
+```json
+{
+  "tool": "call_mcp",
+  "arguments": {
+    "connection": "cyberchef",
+    "tool": "cyberchef_magic",
+    "arguments": {
+      "input": "ZXlKaGJHY2lPaUpTVXpVbkxh..."
+    }
+  }
+}
+```
+
+### 2. Sequential Multi-Layer Deobfuscation (`cyberchef_bake`)
+For payloads with layered obfuscation (e.g. Hex inside Base64 inside URL-encoded query params):
+```json
+{
+  "tool": "call_mcp",
+  "arguments": {
+    "connection": "cyberchef",
+    "tool": "cyberchef_bake",
+    "arguments": {
+      "input": "%34%38%36%35%36%63%36%63%36%66",
+      "recipe": [
+        { "op": "URL Decode" },
+        { "op": "From Hex", "args": ["None"] }
+      ]
+    }
+  }
+}
+```
+
+### 3. Entropy Assessment & Encoding Representation Calibration
+When evaluating whether a payload or parameter is encrypted, packed shellcode, or benign text, evaluate Shannon entropy through `call_mcp`:
+```json
+{
+  "tool": "call_mcp",
+  "arguments": {
+    "connection": "cyberchef",
+    "tool": "cyberchef_entropy",
+    "arguments": {
+      "input": "01a2fe89cb994821a0d8e4..."
+    }
+  }
+}
+```
+
+> [!IMPORTANT]
+> **Calibrate entropy thresholds by input encoding representation:**
+> Shannon entropy measures bits of information per character. The theoretical maximum is strictly bounded by the alphabet size ($\log_2(N)$):
+> - **Hex Strings (16 characters, max 4.0 bits/char)**:
+>   - *Plain text / formatted Hex*: ~2.5 – 3.2
+>   - *High-entropy ciphertext / encrypted payload*: **3.8 – 4.0** (Cannot exceed 4.0!)
+>   - *Warning*: Do not misclassify hex ciphertext scoring ~3.9 as low-entropy content.
+> - **Base64 Strings (64 characters, max 6.0 bits/char)**:
+>   - *Plain text Base64*: ~3.8 – 4.5
+>   - *High-entropy ciphertext / packed data*: **5.7 – 6.0** (Cannot exceed 6.0!)
+> - **Raw Binary / Decoded Byte Streams (256 values, max 8.0 bits/byte)**:
+>   - *Plain text / uncompressed source code*: < 4.5
+>   - *Compressed archives / packed code / encrypted shellcode*: > 7.2
+>
+> **Best Practice**: Decode encoded representations (Hex, Base64) to raw bytes via `cyberchef_from_hex` or `cyberchef_from_base64` before evaluating raw Shannon entropy.
+
+## Common Security Analysis Patterns
+
+### Pattern 1: Nested WAF Bypass / Obfuscated Injection Vector
+When target web applications accept encoded input in parameters or cookies:
+1. Extract candidate parameter from HTTP request or response.
+2. Call `call_mcp(connection="cyberchef", tool="cyberchef_magic", arguments={"input": candidate})` to determine layers.
+3. Call `call_mcp(connection="cyberchef", tool="cyberchef_bake", arguments={"input": candidate, "recipe": [...]})` with the suggested pipeline to recover the plaintext injection string.
+4. Verify whether the underlying query contains unsanitized SQLi (`UNION SELECT`), XSS, or SSRF vectors.
+
+### Pattern 2: JWT Security Inspection
+When encountering `Authorization: Bearer <token>` or session tokens:
+1. Call `call_mcp(connection="cyberchef", tool="cyberchef_jwt_decode", arguments={"token": token})`.
+2. Inspect the header: check for `alg: "none"`, `alg: "HS256"` with potential asymmetric public key confusion, or empty signatures.
+3. Inspect claims: verify expiry timestamps (`exp`), issuer (`iss`), role/privilege elevations, and user identities.
+
+### Pattern 3: XOR Obfuscation Recovery
+When inspecting hardcoded binary strings, PowerShell scripts, or obfuscated malware droppers:
+1. Identify probable key length or common plaintext prefix (e.g., `MZ`, `http`, `function`).
+2. Run `call_mcp(connection="cyberchef", tool="cyberchef_xor", arguments={"input": data, "key": candidate_key})` iterating candidate keys to extract underlying C2 endpoints or script payloads.
+
+## Critical Correctness Rules
+
+- **Use `call_mcp` Dispatch**: Never attempt to call CyberChef tools directly as top-level agent tools. Always dispatch through `call_mcp(connection="cyberchef", tool="...", arguments={...})`.
+- **Do Not Guess Encodings**: If a string contains `=, %, 0x` or unexpected symbols, run `cyberchef_magic` first rather than blindly applying base64 or URL decoding.
+- **Preserve Raw Inputs**: Keep the original obfuscated string in agent memory/notes alongside the decoded output for accurate proof-of-concept (PoC) reporting.
+- **Fail-Safe Fallback**: If an operation fails during `cyberchef_bake`, isolate the failing recipe step and execute individual tools (`cyberchef_from_base64`, `cyberchef_url_decode`) sequentially via `call_mcp`.
+- **Safe Defanging**: Always run `cyberchef_defang_url` via `call_mcp` on confirmed malicious or C2 URLs before writing final markdown reports.
+
+## Failure Recovery
+
+- If `cyberchef_from_base64` throws a padding error, retry with `urlSafe: true` or inspect whether characters are URL percent-encoded first.
+- If `cyberchef_from_hex` produces unprintable characters, check if the input is big-endian or uses custom delimiters (`0x`, `Space`, `,`).
+- If `call_mcp` returns an unknown tool error, call `search_mcp_tools(connection="cyberchef", query="...")` to discover the exact tool names registered by the server.
+
+If uncertain, query web_search with:
+`site:gchq.github.io/CyberChef cyberchef <operation_name>`