diff --git a/Cargo.lock b/Cargo.lock
index 4b1cdad..7ea46e2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -468,6 +468,12 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
 
+[[package]]
+name = "base64"
+version = "0.22.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72b3254f16251a8381aa12e40e3c4d2f0199f8c6508fbecb9d91f575e0fbb8c6"
+
 [[package]]
 name = "bit-set"
 version = "0.8.0"
@@ -660,6 +666,7 @@ dependencies = [
  "iana-time-zone",
  "js-sys",
  "num-traits",
+ "serde",
  "wasm-bindgen",
  "windows-link 0.2.1",
 ]
@@ -849,6 +856,40 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f27ae1dd37df86211c42e150270f82743308803d90a6f6e6651cd730d5e1732f"
 
+[[package]]
+name = "darling"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25ae13da2f202d56bd7f91c25fba009e7717a1e4a1cc98a76d844b65ae912e9d"
+dependencies = [
+ "darling_core",
+ "darling_macro",
+]
+
+[[package]]
+name = "darling_core"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9865a50f7c335f53564bb694ef660825eb8610e0a53d3e11bf1b0d3df31e03b0"
+dependencies = [
+ "ident_case",
+ "proc-macro2",
+ "quote",
+ "strsim",
+ "syn",
+]
+
+[[package]]
+name = "darling_macro"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3984ec7bd6cfa798e62b4a642426a5be0e68f9401cfc2a01e3fa9ea2fcdb8d"
+dependencies = [
+ "darling_core",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "dispatch"
 version = "0.2.0"
@@ -906,6 +947,12 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d8b14ccef22fc6f5a8f4d7d768562a182c04ce9a3b3157b91390b52ddfdf1a76"
 
+[[package]]
+name = "dyn-clone"
+version = "1.0.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0881ea181b1df73ff77ffaaf9c7544ecc11e82fba9b5f27b262a3c73a332555"
+
 [[package]]
 name = "ecolor"
 version = "0.33.3"
@@ -1236,12 +1283,48 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b147ee9d1f6d097cef9ce628cd2ee62288d963e16fb287bd9286455b241382d"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07bbe89c50d7a535e539b8c17bc0b49bdb77747034daa8087407d655f3f7cc1d"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+]
+
 [[package]]
 name = "futures-core"
 version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7e3450815272ef58cec6d564423f6e755e25379b217b0bc688e295ba24df6b1d"
 
+[[package]]
+name = "futures-executor"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf29c38818342a3b26b5b923639e7b1f4a61fc5e76102d4b1981c6dc7a7579d"
+dependencies = [
+ "futures-core",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-io"
 version = "0.3.32"
@@ -1272,6 +1355,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "futures-sink"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c39754e157331b013978ec91992bde1ac089843443c49cbc7f46150b0fad0893"
+
 [[package]]
 name = "futures-task"
 version = "0.3.32"
@@ -1284,9 +1373,13 @@ version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
 dependencies = [
+ "futures-channel",
  "futures-core",
+ "futures-io",
  "futures-macro",
+ "futures-sink",
  "futures-task",
+ "memchr",
  "pin-project-lite",
  "slab",
 ]
@@ -1631,6 +1724,12 @@ version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3d3067d79b975e8844ca9eb072e16b31c3c1c36928edf9c6789548c524d0d954"
 
+[[package]]
+name = "ident_case"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
+
 [[package]]
 name = "idna"
 version = "1.1.0"
@@ -1918,6 +2017,9 @@ dependencies = [
  "fastrand",
  "insta",
  "regex",
+ "rmcp",
+ "serde",
+ "tokio",
 ]
 
 [[package]]
@@ -2379,6 +2481,12 @@ version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 
+[[package]]
+name = "pastey"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b867cad97c0791bbd3aaa6472142568c6c9e8f71937e98379f584cfb0cf35bec"
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.2"
@@ -2598,6 +2706,26 @@ dependencies = [
  "bitflags 2.11.0",
 ]
 
+[[package]]
+name = "ref-cast"
+version = "1.0.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f354300ae66f76f1c85c5f84693f0ce81d747e2c3f21a45fef496d89c960bf7d"
+dependencies = [
+ "ref-cast-impl",
+]
+
+[[package]]
+name = "ref-cast-impl"
+version = "1.0.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b7186006dcb21920990093f30e3dea63b7d6e977bf1256be20c3563a5db070da"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "regex"
 version = "1.12.3"
@@ -2633,6 +2761,41 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "19b30a45b0cd0bcca8037f3d0dc3421eaf95327a17cad11964fb8179b4fc4832"
 
+[[package]]
+name = "rmcp"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba6b9d2f0efe2258b23767f1f9e0054cfbcac9c2d6f81a031214143096d7864f"
+dependencies = [
+ "async-trait",
+ "base64",
+ "chrono",
+ "futures",
+ "pastey",
+ "pin-project-lite",
+ "rmcp-macros",
+ "schemars",
+ "serde",
+ "serde_json",
+ "thiserror 2.0.18",
+ "tokio",
+ "tokio-util",
+ "tracing",
+]
+
+[[package]]
+name = "rmcp-macros"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ab9d95d7ed26ad8306352b0d5f05b593222b272790564589790d210aa15caa9e"
+dependencies = [
+ "darling",
+ "proc-macro2",
+ "quote",
+ "serde_json",
+ "syn",
+]
+
 [[package]]
 name = "rustc-hash"
 version = "1.1.0"
@@ -2686,6 +2849,32 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "schemars"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a2b42f36aa1cd011945615b92222f6bf73c599a102a300334cd7f8dbeec726cc"
+dependencies = [
+ "chrono",
+ "dyn-clone",
+ "ref-cast",
+ "schemars_derive",
+ "serde",
+ "serde_json",
+]
+
+[[package]]
+name = "schemars_derive"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7d115b50f4aaeea07e79c1912f645c7513d81715d0420f8bc77a18c6260b307f"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "serde_derive_internals",
+ "syn",
+]
+
 [[package]]
 name = "scoped-tls"
 version = "1.0.1"
@@ -2747,6 +2936,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serde_derive_internals"
+version = "0.29.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18d26a20a969b9e3fdf2fc2d9f21eda6c40e2de84c9408bb5d3b05d499aae711"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "serde_json"
 version = "1.0.149"
@@ -3058,6 +3258,41 @@ dependencies = [
  "zerovec",
 ]
 
+[[package]]
+name = "tokio"
+version = "1.50.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "27ad5e34374e03cfffefc301becb44e9dc3c17584f414349ebe29ed26661822d"
+dependencies = [
+ "bytes",
+ "pin-project-lite",
+ "tokio-macros",
+]
+
+[[package]]
+name = "tokio-macros"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c55a2eff8b69ce66c84f85e1da1c233edc36ceb85a2058d11b0d6a3c7e7569c"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "tokio-util"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ae9cec805b01e8fc3fd2fe289f89149a9b66dd16786abd8b19cfa7b48cb0098"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-sink",
+ "pin-project-lite",
+ "tokio",
+]
+
 [[package]]
 name = "toml_datetime"
 version = "0.7.5+spec-1.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index fb1bb97..e187472 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,6 +10,9 @@ clap = { version = "4.5", features = ["derive"] }
 chrono = "0.4"
 regex = "1.10"
 fastrand = "2.3"
+rmcp = { version = "1.2", features = ["server", "transport-io"] }
+tokio = { version = "1", features = ["rt", "io-std", "macros"] }
+serde = { version = "1", features = ["derive"] }
 
 [dev-dependencies]
 insta = { version = "1.39", features = ["yaml"] }
diff --git a/docs/BNF.md b/docs/BNF.md
index e6ecc1a..3d1af8a 100644
--- a/docs/BNF.md
+++ b/docs/BNF.md
@@ -147,11 +147,11 @@ The Myc runtime environment provides a collection of built-in functions and macr
 (do
   ;; Create a series with a typed layout (Struct-of-Arrays under the hood)
   (def my_ticks (series {:price :float :volume :int :msg :text}))
-  
+
   (push my_ticks {:price 10.5 :volume 100 :msg "A"})
   (push my_ticks {:price 11.2 :volume 200 :msg "B"})
   (push my_ticks {:price 15.5 :volume 300 :msg "C"})
-  
+
   ;; Extract the price series specifically
   (def prices (.price my_ticks))
 
@@ -159,3 +159,123 @@ The Myc runtime environment provides a collection of built-in functions and macr
   (+ (prices 0) (prices 1)) ;; Output: 26.7
 )
 ```
+
+## 8. Common Mistakes & Pitfalls
+
+This section is especially relevant for LLMs generating Myc code.
+
+### Wrong keywords from other Lisps
+
+| Wrong (Clojure/Scheme) | Correct Myc |
+|---|---|
+| `(let [x 1] ...)` | `(do (def x 1) ...)` |
+| `(begin ...)` | `(do ...)` |
+| `(lambda [x] ...)` | `(fn [x] ...)` |
+| `(define x 1)` | `(def x 1)` |
+| `(set! x 2)` | `(assign x 2)` |
+| `(cond ...)` | nested `(if ...)` |
+| `(not= a b)` | `(<> a b)` |
+
+### Series indexing is reversed
+
+Index `0` is the **most recently pushed** item, not the oldest. This is the opposite of normal array indexing:
+
+```clojure
+(push s {:v 1})
+(push s {:v 2})
+(push s {:v 3})
+;; ((.v s) 0) => 3  (newest)
+;; ((.v s) 1) => 2
+;; ((.v s) 2) => 1  (oldest)
+```
+
+### Record keys must be keywords, not strings
+
+```clojure
+;; WRONG:
+{"price" 10.5}
+
+;; CORRECT:
+{:price 10.5}
+```
+
+### `again` is only valid inside `fn`
+
+`(again ...)` jumps back to the enclosing `fn`. Using it outside a function is a compile error.
+
+```clojure
+;; WRONG — top-level again:
+(again 1 2)
+
+;; CORRECT — inside fn:
+(fn [n] (if (= n 0) "done" (again (- n 1))))
+```
+
+### `check_syntax` accepts only a single expression
+
+The `check_syntax` tool uses the single-expression compiler pass. Wrap multiple expressions in `(do ...)`:
+
+```clojure
+;; WRONG:
+(def x 1) (+ x 2)
+
+;; CORRECT:
+(do (def x 1) (+ x 2))
+```
+
+### Field accessors are functions, not property syntax
+
+```clojure
+;; WRONG — not valid syntax:
+user.name
+
+;; CORRECT — field accessor called as a function:
+(.name user)
+
+;; Also correct — extract accessor first, then call:
+(def get-name .name)
+(get-name user)
+```
+
+**Recursive Function with Tail-Call Optimization:**
+```clojure
+(do
+  ;; Factorial using explicit TCO via (again ...) — like Clojure's recur
+  (def factorial
+    (fn [n acc]
+      (if (= n 0)
+        acc
+        (again (- n 1) (* acc n)))))
+
+  (factorial 10 1) ;; Output: 3628800
+)
+```
+
+**Macro Definition:**
+```clojure
+(do
+  ;; Define a macro that inverts a condition
+  (macro unless [c body]
+    `(if ~c ... ~body))
+
+  (unless false "executed") ;; Output: "executed"
+)
+```
+
+**Series with while Loop:**
+```clojure
+(do
+  (def ticks (series {:price :float}))
+  (def i 0)
+
+  ;; Push 5 prices into the series
+  (while (< i 5)
+    (do
+      (push ticks {:price (* i 1.5)})
+      (assign i (+ i 1))))
+
+  ;; Read back the two most recent prices
+  (def p (.price ticks))
+  (+ (p 0) (p 1)) ;; newest + second-newest
+)
+```
diff --git a/src/ast/environment.rs b/src/ast/environment.rs
index e00fdc6..a0da692 100644
--- a/src/ast/environment.rs
+++ b/src/ast/environment.rs
@@ -600,6 +600,19 @@ impl Environment {
     }
 
 
+    /// Returns the names of all bindings registered in the fixed RTL scope.
+    /// Useful for introspection (e.g., MCP server listing available built-ins).
+    pub fn list_bindings(&self) -> Vec<String> {
+        let root_scopes = self.root_scopes.borrow();
+        let mut names: Vec<String> = root_scopes[0]
+            .locals
+            .keys()
+            .map(|sym| sym.name.to_string())
+            .collect();
+        names.sort();
+        names
+    }
+
     pub fn dump_ast(&self, source: &str) -> Result<String, String> {
         self.preload_dependencies(source, None)?;
         let compiled = self.compile(source).into_result()?;
diff --git a/src/ast/mod.rs b/src/ast/mod.rs
index 2307e48..39ddc02 100644
--- a/src/ast/mod.rs
+++ b/src/ast/mod.rs
@@ -3,6 +3,7 @@ pub mod compiler;
 pub mod diagnostics;
 pub mod environment;
 pub mod lexer;
+pub mod mcp_server;
 pub mod nodes;
 pub mod parser;
 pub mod rtl;
diff --git a/src/bin/ast.rs b/src/bin/ast.rs
index 7ecbb53..d73cd0e 100644
--- a/src/bin/ast.rs
+++ b/src/bin/ast.rs
@@ -39,10 +39,22 @@ struct Cli {
     /// Disable optimization
     #[arg(long)]
     no_opt: bool,
+
+    /// Start MCP server (stdio transport, for LLM integration)
+    #[arg(long)]
+    mcp: bool,
 }
 
 fn main() {
     let cli = Cli::parse();
+
+    if cli.mcp {
+        if let Err(e) = myc::ast::mcp_server::run() {
+            eprintln!("MCP server error: {}", e);
+            std::process::exit(1);
+        }
+        return;
+    }
     let mut env = Environment::new();
     env.optimization = !cli.no_opt;